强化lecture one 1

托福听力tpo50 lecture1、2、3、4 原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (4)答案 (6)译文 (6)Lecture2 (8)原文 (8)题目 (10)答案 (12)译文 (12)Lecture3 (14)原文 (14)题目 (16)答案 (18)译文 (18)Lecture4 (20)原文 (20)题目 (22)答案 (24)译文 (24)Lecture1原文NARRATOR: Listen to part of a lecture in an ancient history class.FEMALE PROFESSOR: OK, last time we were discussing trade and commerce during the Bronze Age … And I said a little over 3,000 years ago there was quite a lively trade among the countries along the Mediterranean Sea—people were making objects out of bronze, and they were using bronze tools to make other goods, and they developed trade networks to trade these goods with other countries around the Mediterranean … One of the things they traded was glass …And recently there was an archeological excavation in Egypt—on the Nile River, around where it enters the Mediterranean Sea—where they discovered an ancient glass factory. Robert?MALE STUDENT: I thought our textbook said that the Egyptians imported their glass from other countries.FEMALE PROFESSOR: Well, until now that's what the evidence seemed to suggest. I mean, we had some evidence that suggested that the Egyptians were making glass objects, uh, but not glass.MALE STUDENT: OK, am-am I missing something? They're making glass, but they're not making glass.FEMALE PROFESSOR: I said they were making glass objects, right? You see, it was previously thought that they weren't actually making the raw glass itself, that they were importing unfinished glass from Mesopotamia—um, which today is a region consisting of Iraq, and parts of Syria, Turkey, and Iran—and simply reworking it. Most archeologists believed that the glass factories were in Mesopotamia because that's where the oldest known glass remains come from. You see, there were two stages of glassmaking: the primary production stage, where they made disks of raw glass… Uh, an- and then there was the secondary stage, where they melted the raw glass, the glass disks, and created decorative objects or whatever.And from this new Egyptian site we've learned that the primary production stage had several steps. First, they took quartz—a colorless, transparent mineral—and crushed it. Then they took that crushed quartz and mixed it with plant ash; uh, “plant ash” is just what it soundslike—the ash that's left after you've burned plant material. They slowly heated this mixture, at a relatively low temperature, in small vessels, um containers, like jars, made out of clay. Uh, and that yielded a kind of glassy material…They took this glassy material and ground it up into a powder, and then they used metallic dye to color it… After that, they poured the colored powder out into disk-shaped molds and heated it up to very high temperatures, so that it melted. After it cooled, they'd break the molds, and inside…there were the glass disks. These disks were shipped off to other sites within Egypt and places around the Mediterranean. Then, in the secondary phase, the disks were reheated and shaped into decorative objects. Susan?FEMALE STUDENT: So what kind of objects were people making back then? FEMALE PROFESSOR: Well, the most common objects we’ve found—mostly in Egypt and Mesopotamia—uh, the most common objects were beads; one thing Egyptians were very, very good at was imitating precious stones; they created some beads that looked so much like emeralds and pearls that it was very difficult to distinguish them from the real thing. Uh, and-and also beautiful vessels, uh, with narrow necks; they were probably really valuable, so they wouldn't have been used to hold cooking oil or common food items; they were most likely used for expensive liquids like perfume. Now the glass made at this factory was mostly red; to get this red color, they used copper; in a sophisticated process. Of course, any kind of glass was very valuable, so these red bottles would only have been owned by wealthy people. In fact, because it was so difficult to make, and sort of mysterious and complicated, it was probably a product produced for the royal family, and they probably used glass to show their power. Also, beautiful, expensive objects make great gifts if you're looking to establish or strengthen political alliances…and it's quite possible that ancient Egyptians were actually exporting glass, not just making it or importing it. The trade with Mesopotamia was probably a friendly, mutual trade…because, uh, Mesopotamian glass was usually white or yellow, so Mesopotamians might have said something like, “We'll give you two white disks for two red disks.” There’s no proof ofthat, uh—at least not yet…题目1.What is the lecture mainly about?A. New information about glass production and use in ancient EgyptB. Whether Egyptians or Mesopotamians were the first to invent glassC. Differences between Egyptian glass and other kinds of glassD. Reasons why ancient Egyptians imported glass from other countries2.What is the importance of the archaeological evidence recently found in Egypt?A. It supports the theory that ancient Egyptians imported glass from Mesopotamia.B. It proves that ancient Egyptians made glass objects prior to the Bronze Age.C. It provides the first evidence that glassmaking in the Bronze Age required two different stages.D. It shows that ancient Egyptians were producing raw glass.3.The professor describes a process for making glass disks. Summarize the process by putting the steps in the correct order. [Click on a sentence. Then drag it to the space where it belongs. The last one is done for you.]A.Glass-like material is ground up and dyed blue or red.B.Powdered material is heated at very high temperatures.C.Crushed quartz and plant ash are heated at low temperatures.D.Containers are broken to remove glass disks.4.Based on the lecture, what are two kinds of glass objects that were valued in ancient Egypt and Mesopotamia? [Click on 2 answers.]A. BeadsB. Cooking utensilsC. ContainersD. Windows5.According to the professor, what are two reasons why ancient Egyptians exported glass? [Click on 2 answers.]A. To build relationships with foreign leadersB. To hold cooking oil that was sold in other countriesC. To get bronze tools from other countriesD. To acquire colors of glass not made in Egypt6.Why does the professor say this:Robert: Ok. Am……Am I missing something? They are making glass but they are not making glass?Professor: I said they were making glass objects, right?A. To emphasize that glass objects were only made in ancient EgyptB. To find out what the student does not understandC. To indicate that there was no contradiction in her previous statementD. To correct what she said in her previous statement答案A D CABD AC AD C译文旁白：请听一个古代历史课上的讲座片段。

托福听力tpo40lecture1、2、3、4原文+题目+答案+译文Lecture1 (2)原文 (2)题目 (4)答案 (5)译文 (6)Lecture2 (7)原文 (7)题目 (9)答案 (11)译文 (11)Lecture3 (13)原文 (13)题目 (16)答案 (18)译文 (18)Lecture4 (20)原文 (20)题目 (22)答案 (24)译文 (24)Lecture1原文NARRATOR:Listen to part of a lecture in an art history class.MALE PROFESSOR:Last class I passed out your assignment for your first paper,and today I want to spend some time going over it.Mm…most people never take any art history until they get to college,so many of you have probably never written an art history paper before.I gave you a list of appropriate works of art for you to write about.So your next step in this process needs to be to go look at the work you've selected as your topic.And bring a pencil and a notepad with you,because I don't mean you should just drop by at the museum and glance at it so you can say you've seen it in real life.You need to go and sit in front of the work and really look at it—carefully and slowly.And keep careful notes about what you see—you’ll need them for the kind of art history paper you're going to be writing…it's what we call a formal analysis.A formal analysis of a work of art,any kind of art,is based on its formal qualities, which means qualities related to the form—things like color…texture…line…shapes…proportion…and composition.Probably the closest thing to a formal analysis you might have written is for an English class.If you've…say…written an analysis of a poem,you've used the same skills—you've given an analysis of the poem by describing and analyzing its form and meter.A formal analysis paper in art history is very similar.Now,before you begin writing your formal analysis,you'll want to start with a summary of the overall appearance of the work—a brief description of what you see. Are there figures—people?What are they doing?Or is it a landscape…or an abstract representation of something?Tell what the subject is,and what aspects are emphasized in the painting.This will give your reader an overview of what the work looks like before you analyze it.The next part of your paper—the actual formal analysis—will be the longest and most important section of your paper,where you describe and analyze individual design elements.For this portion of the paper,you're going to rely on the notes you took at the museum,because you should be able to describe in detail the design elements the artist uses,and how they are used.For example,does the artist use harsh lines or soft lines—are the colors bright or muted?Focus on the design elements that you feel are most strongly represented in that particular work of art. And if you don't know where to begin,take note of where your eye goes first.Then describe things in the order in which your eye moves around the work.This will help you understand how one part relates to another—the interaction between the different parts of the work.OK,this kind of analysis should occur throughout the main portion of the paper.In the last section of your paper—and this goes beyond formal analysis—you comment on the significance of what you have seen.What details of the work convey meaning?Some significant details will not be apparent to you right away,but if you look long enough,you realize how important they are for your interpretation of the work.Many years ago,I was writing a formal analysis of a painting of a little boy.In the painting,a little boy was standing in his nursery,and he was holding a toy bird in his hand,and there were more toys around him in the background of the painting. Because of the bird he was holding,I assumed at first that the painting was about the innocence of children.But as I looked at the painting longer,I realized that the boy's eyes looked sad even though there was no discernable expression on his face.And then it dawned on me that,even though he was surrounded by toys,he was all alone in his nursery.The boy's eyes were a significant detail in the painting,that I didn't notice at first.题目1.What point does the professor make about the writing of a formal analysis in art history?A.Its objective is to identify common features of several works of art.B.Its most important part is the explanation of an artwork's significance.C.Several styles of writing a formal analysis are used by art historians.D.A particular approach is required to present Information about an artwork.2.According to the professor,what will students need to do before writing the art history paper?A.Look at examples of formal analysis in textbooksB.Take notes on the artwork they will write aboutC.Go to different museums before selecting a topic for the paperD.Study the historical context of the artwork they will write about3.Why does the professor mention an English class?A.To explain the difference between visual language and written languageB.To explain that students need good writing skills for their assignmentC.To point out similarities between a poetry paper and the students'assignmentD.To point out that many art historians become writers4.What does the professor recommend as a way to understand the relationship between different parts of an artwork?A.Looking for lines that connect different parts of the workB.Examining the artwork from several different anglesC.Looking for similar colors the artist used throughout the workD.Determining how the viewer's eyes move around the work5.Why does the professor talk about his own experience analyzing the painting of a little boy?A.To point out a common misconception about formal analysisB.To stress the importance of looking at an artwork thoroughlyC.To show why a formal analysis should not emphasize small detailsD.To provide an example of an artwork that is easy to analyze6.The professor describes three sections the art history paper should contain.Place them in the order in which they should appear in the paper.Click on a phrase.Then drag it to the space where it belongs.A.Analysis of the design elements the artist usesB.Discussion of the meaning of the artworkC.Summary of the appearance of the artwork答案D B C D B CAB译文旁白：下面听一段艺术史课程的片段。

Lecture 1 Introduction to lexicologyObjectivesAfter learning the lecture, you are expected to be able to answer the following questions:? How to interpret and distinguish the terms with ‘lexi-’?？What is lexicology?? How can lexicology be classified?? What does lexicology study?? What is English lexicology?? What are the two approaches to the study of English lexicology?? What is the character of the English language?? What are the characteristics of English words/vocabulary?? How is lexicology connected with other branches of linguistics?Interpretation of some terms in lexicology1.Lexicon & lexis: the total bank of words and phrases of a particular language, the artifact ofwhich is known as a lexicon.2.Lexeme: A lexeme is an abstract unit of morphological analysis in linguistics, that roughlycorresponds to a set of forms taken by a single word. For example, in the English language, run, runs, ran and running are forms of the same lexeme, conventionally written as RUN.[1]In order to reduce the ambiguity of the term ‘word’, the term ‘lexeme’is postulated as an abstract unit which refers to the smallest unit that can be distinguished from other smaller units. A lexeme can occur in many different forms in actual spoken and written texts. For example, ‘write’ is the lexeme of the following words: write, writes, wrote, written, writing. 3.Lexical units: Lexical items composed of more than one word are also sometimes calledlexical chunks, gambits, lexical phrases, lexical units, lexicalized stems or speech formulae.4.Word is the smallest free form (an item that may be uttered in isolation with semantic orpragmatic content) in a language, in contrast to a morpheme, which is the smallest unit of meaning. A word may consist of only one morpheme (e.g. wolf), but a single morpheme may not be able to exist as a free form (e.g. the English plural morpheme -s).Typically, a word will consist of a root or stem, and zero or more affixes. Words can be combined to create other units of language, such as phrases, clauses, and/or sentences.5.lexicology:●Lexicology (from lexiko-, in the Late Greek lexikon) is that part of linguistics which studieswords, their nature and meaning, words' elements, relations between words (semantical relations), words groups and the whole lexicon.●Lexicology is a branch of linguistics concerned with the study of the vocabulary of a givenlanguage. It deals with words, their origin, development, history, structure, meaning and application. In short, it is the study of the signification and application of words.6.Lexicology has developed such branches asa)semantics——study of meaning of words (and sentences)b)etymology——study of origins of wordsc)historical lexicology——study of the development of vocabulary as a whole on the basisof etymology and other sciencesd)phraseology——study of individual words and set expressions, stock phrases, cast-ironidioms, i.e. the study of formation and usage, classification and characteristics of idiomse)lexicography——study of the form, meaning, usage, origin of vocabulary and themaking of dictionaries7.lexicographyA good example of lexicology at work, that everyone is familiar with, is that of dictionariesand thesaurus. Dictionaries are books or computer programs (or databases) that actually represent lexicographical work, they are opened and purposed for the use of public.A thesaurus is a work that lists words grouped together according to similarity ofmeaning (containing synonyms and sometimes antonyms), in contrast to adictionary, which contains definitions and pronunciations. The largest thesaurus in the world is the Historical Thesaurus of the Oxford English Dictionary, which contains more than 920,000 words and meanings.A dictionary is a collection of words in a specific language, often listed alphabetically, withusage information, definitions, etymologies, phonetics, pronunciations, and other information;or a book of words in one language with their equivalents in another, also known as a lexicon. Exercise 1Exercise 2accept (accepted, accepted, accepting)__________ lexemes__________ word forms__________ lexical units__________ wordsExercise 3Use examples to tell the different branches of lexicology. For example, in English, many roots and affixes are from Latin or Greek. This is the branch etymology.How can lexicology be classified?General lexicology & Special lexicologyDistinction is made between GENERAL LEXICOLOGY & SPECIAL LEXICOLOGY. General lexicology is a part of General linguistics. It is concerned with the study of vocabulary irrespective of the specific features of any particular language. Special lexicology is the lexicology of a particular language (Russian, German, French, etc.).Research methods of English lexicologyThere are two main approaches to the study of English lexicology, that is, synchronic and diachronic.The term ‘synchronic’means describing a language as it exists at one point in time. The term diachronic means, concerned with historical development of a language.A synchronic approach is an approach to the study of a language at one period of time, whereas a diachronic approach is an approach to the study of the change in a language that took place over a period of time.Character of the English languageThe English language is of a mixed character. On the one hand, it shares with West Germanic languages many common words and similar grammatical structures. On the other hand, more than half of the English vocabulary is derived from Latin and French. Besides, English has accepted words from other languages of the world in the course of historical development.Characteristics of English vocabulary or words1.Native words are the foundation and the core of the English vocabulary. In structure they aremostly monosyllabic words. In meaning they express the fundamental concepts dealing with everyday objects and things. In grammar they include most parts of speech. Native words have the following three characteristics: 1) the polysemous character; 2) the collocability; and3) word-formation ability.2.There is large amount of English vocabulary. There are3.There are various Englishes all over the world.4.and it is increasing at a surprising speed.5.…How is lexicology connected with other branches of linguistics?1)with phoneticsPhonetics is closely related wit lexicology. Without sound there is word because every word is a unity of sound and meaning.2)with grammarV ocabulary and grammar are originally related to one another. In learning language, attention to grammar is as important as attention to vocabulary. The vocabulary of a language assumes tremendous importance when it comes under the control of grammar, which is concerned with the modification in form of words and the combination of words into sentences.3)with stylisticsLexicology studies stylistic variants on the basis of meanings of words and their changes, synonyms, antonyms, figures of speech etc.Exercise 41.The words such as ‘export’, ‘increase’, ‘process’ and ‘progress’ with different pronunciationserve different parts of speech, which indicates that lexicology is connected with __________.2.In the sentence ‘O ther school managers are also eyeing the program’, we study the word ‘eye’,which shows that lexicology is connected with _______.3.Bill Gates and his friend Paul Allen laid the first brick in the foundation of Microsoft.4.The word advisable in ‘It is advisable that we take immediate measures to enhance teaching’can’t be replaced by advise or advice, which demonstrates that lexicology is related to _______.Exercise 5Fill in the blanks to consolidate your understanding of the terms in the unit.1.The artifact of the total bank of words and phrases of a particular language is called_________.2. A _________is an abstract unit of morphological analysis in linguistics, that roughlycorresponds to a set of forms taken by a single word.3._________is the smallest free form (an item that may be uttered in isolation withsemantic or pragmatic content) in a language.4._________is a branch of linguistics concerned with the study of the vocabulary of agiven language. It deals with words, their origin, development, history, structure, meaning and application.5._________ is a study of origins of words6._________ is a study of the form, meaning, usage, origin of vocabulary and the makingof dictionaries.7. A _________ is a work that lists words grouped together according to similarity ofmeaning (containing synonyms and sometimes antonyms), in contrast to a dictionary, which contains definitions and pronunciations.8._________lexicology is a part of General linguistics. It is concerned with the study ofvocabulary irrespective of the specific features of any particular language.9._________lexicology is the lexicology of a particular language (Russian, German,French, etc.).10.There are two main approaches to the study of English lexicology, that is, _________and diachronic.11.The term ‘_________’ means describing a language as it exists at one point in time. Theterm _________ means, concerned with historical development of a language.12.A _________ approach is an approach to the study of a language at one period of time,whereas a diachronic approach is an approach to the study of the change in a language that took place over a period of time.13.Lexicology studies stylistic variants on the basis of meanings of words and their changes,synonyms, antonyms, figures of speech etc. in this case, we say that lexicology is connected with _________.。

托福听力tpo63lecture1、2、3原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (3)答案 (5)译文 (5)Lecture2 (7)原文 (7)题目 (9)答案 (11)译文 (11)Lecture3 (13)原文 (13)题目 (15)答案 (17)译文 (17)Lecture1原文Listen to part of a lecture in a geology class.Professor:OK.Before we begin,I wanna remind you that our field trip to Bryce canyon national park is this weekend.Remember the bus leaves early,five am,so don't forget to set your alarm clocks.I think you're all gonna enjoy getting out of the classroom and actually seeing some remarkable geologic phenomena.Now,while we're there,I want you to pay particular attention to two things.One obviously will be the sediment layers making up the rocks,since we've spent so much time onsedimentary rocks.Bryce canyon is a great place to see how millions of years have turned layers and layers of tightly packed sediment,mud particles,sand remains of plants and animals into rock.But you're also gonna see some fascinating rock shapes, formations that are the result of the weathering and the erosion processes that occur at Bryce canyon.There are two main processes that are important.The first one is a weathering process called frost wedge.Frost wedge a process that widens cracks in rocks in the wintertime.It begins with warm air or daytime sun melting the snow.As the snow turns into water,it seeps into the cracks that occur naturally in sedimentary rocks.At night,this water freezes in the cracks,but when water freezes,it expands quite a bit, which means that it prize cracks open,gradually,making them wider and breaking off a little bits in the process.Now,this thought freeze cycle can happen as many as two hundred times in a single year.So that makes it the most important weathering process at Bryce canyon.The other key processes is runoff,which is an erosion process.Runoff takes place in the summer.The parks in the desert said the grounds very dry.When it rains in late summer,the ground is too hard to absorb the water,so it runs off.And as it runs off, it carries away the gravel,the broken bits of rock created by cross wedge in the winter.So runoff is the main erosion process that alters the rock landscape in the park.And because these processes have occurred over thousands of years,some of the results can be pretty dramatic,like the giant corridors are passage ways that have developed within the rocks.These passage ways are known as slot canyons.Here's an example of one,not from the part we're going to.This one is actually in Australia,but the scale is typical.So these huge spaces started out as small cracks throughout the sedimentary rock,then thanks to millions of cycles across wedge and runoff.What used to be one big area of rock is now sort of two smaller areas of brought with the corridor in between.We'll have a chance to walk through some like this.These slot canyons are great places to explore,but let me just say,for any of you who aren't from around here,if you ever go on your own,make sure you check aweather forecast first.A sudden heavy rain can cause a flash flood in a slot canyon. So you want to know when it's safe to explore them.Unfortunately,it'll be dry this weekend.Now,these deep,narrow slots are pretty common.You might even have two of them very close to each other with only a thin wall of rock in between.Of course,frost wedge is still at work,so it starts wearing away at the front of the thin wall until you get a whole I mean a hole all the way through the wall,front to back.And this hole gets bigger and bigger.Once it's at least one meter in diameter,it's called a window.And eventually the weight on top of it is just too much,so the roof caves in and only the sides,sometimes it's just one side is left standing.These sides,which look a lot like collins,now are called Hudos.Here's a photo of something we'll be seeing.One of the things that makes Bryce canyon unique is that it has more Hudos than anywhere else in the world.Yes,Margot?Female student:Why is it so lumpy looking?You'd think it would be smoother.Professor:Well,remember,these are sedimentary rocks,so they have layers.Some layers are mostly limestone,and limestone erodes pretty quickly in the presence of any kind of acid.Now Bryce canyon in a very unpolluted area,but even,there the rain water has a little carbolic acid in it,which causes the limestone to erode.But other layers are made up of different types of sediment,which aren't so vulnerable to acid,so they don't erode as quickly.题目1.What is the lecture mainly about?A.The length of time required to produce sedimentary rocksB.The role of climate conditions in the creation of sedimentary rocksC.Some processes that produced a specific group of rock formationsD.Some unique geologic features found in canyons in the United States2.According to the professor,what is one characteristic that frost wedging and runoff share?A.Neither occurs in a desert.B.Neither is a frequent event.C.Both are weathering processes.D.Both are seasonal phenomena.3.Why does the professor show a picture of a slot canyon?A.To give students a sense of the size of a typical slot canyonB.To show students one of the places they will visit on their field tripC.To illustrate how many sediment layers are visible in a typical slot canyonD.To show how much slot canyons can vary based on local climate conditions4.What is the professor's attitude toward students exploring Bryce Canyon on their own?A.He worries that students may not know to take appropriate precautions if they go by themselves.B.He suspects that many students will not go on their own if such a trip requires them to get up early.C.He hopes that the class field trip will motivate students to visit Bryce Canyon on their own.D.He believes that students learn more from individual exploration than they dofrom being in a group.5.How is a hoodoo formed?A.Runoff produces large gravel deposits.B.Air pollution leads to a buildup of limestone.C.The roof of a rock window collapses.D.A flash flood washes away the base of a rock wall.6.According to the professor,what two factors explain why a hoodoo does not have a smooth shape?[Click on2answers.]A.The presence of acid in rainwaterB.The temperature swings between the summer and the winter seasonsC.The composition of the hoodoo's sedimentary layersD.The location of the cracks created by frost wedging答案C D A A C AC译文听一段地质学的讲座。

托福听力tpo64lecture1、2、3原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (3)答案 (5)译文 (5)Lecture2 (7)原文 (7)题目 (9)答案 (11)译文 (11)Lecture3 (13)原文 (13)题目 (15)答案 (17)译文 (17)Lecture1原文Listen to part of a lecture in an economics class.The professor has been talking about international trade.Professor:OK,so let's recap from yesterday.Why do nations engaged in international trade?Well,it's often because of a surplus,more than they need,and they also trade for the opposite reason when they have shortages and can't produce everything they want or need domestically.So these explanations are good as far as they go.But there's another scenario we need to discuss.And that is what if a country is capable of producing something it wants or needs but it can also import the same product from another country?Now,how does the country decide whether to make the product itself or import it?OK,take an example.Um,think about the bananas that you buy in the supermarket.If you look closely,you'll see that most bananas in the United States are imported,imported from countries with tropical climates.But theUnited States has warm regions.It has greenhouse.Clearly,it would be possible to grow bananas here.So why doesn't the US do that?Scott?Student Scott:Well,it is like a lot cheaper and more efficient for countries with tropical climates,for tropical countries to grown bananas,isn't it?I mean,they don't need greenhouse to grow bananas,and they're not so limited to certain regions.Professor:Okay,good.That's exactly right.Tropical countries have what we call an absolute advantage in producing bananas.Absolute advantage is the term we use when a country can produce more of a product using fewer resources.They're the most efficient producer of something.And the United States can't be that with bananas.So it's better off specializing in other goods that it can make more efficiently.Let's take an example,say we have two countries and say they each make only two products and they trade only with each other.Simplistic I know.But well, you'll see where I'm going with this in a moment.OK,so as I was saying,two countries,two products,one country can produce both products more efficiently than the other country.Should these two countries even trade at all?Student Scott:Uh,well,no,I mean,like what's in it for the more efficient country?Professor:Well,what is in it for them?Let's,um,well,let's call these countries um,X and Y.Country X makes both TVs and chairs more efficiently than country Y does.It has an absolute advantage in producing both commodities?No question.But what economists also look at is relative efficiency.And from that perspective,we see that country X is a lot more efficient at making TVs than it is at making chairs and in country Y,ah,well,it turns out they're more efficient at making chairs than TVs.So we say that country Y has a comparative advantage at chair making.And country X has a comparative advantage at TV making.So what should happen?Well,first,both countries should specialize in the production of just one thing.The product they're most efficient at making.Country X should make only TVs and country Y should make only chairs,then two of them should trade.Specialization and trade are going to lead to increase in production and increased overall supply of goods and generally lowerprices.Right?Student Scott:Professor,I still don't see how countries figure out when and where they have a comparative advantage.Professor:Well,you can't fully understand the concept of comparative advantage without also considering the related concept of opportunity cost.Opportunity cost is what you lose,uh,the options you have to give up in order to use your time and resources for something else,countries can determine where their comparative advantages lies,uh,like making TVs instead of chairs by figuring out what they can make with the lowest opportunity cost.Ah,you know,maybe this will be clear if we apply it on a personal level.Now think about when you go out to a movie,your direct monetary cost is the price of the movie ticket.Right?But you also spend two hours at the theater.Your opportunity cost includes both,uh,whatever else you could have spent your money on.Um,ten candy bars may be and whatever else you could have accomplished during the time you were watching the movies,uh,you might have completed your homework for this class,or you might have work two hours overtime at your job,thereby earning instead of spending money.See,these lost possibilities are your opportunity cost.题目1.What is the lecture mainly about?A.Advantages that countries can gain by making their own goodsB.Inequalities that lead to trade imbalances between countriesC.Cost and efficiency concepts that help determine trade decisionsD.Ways in which local surpluses can affect international trade2.Why does the professor talk about growing bananas in countries with tropicalclimates?A.To show how opportunity costs affect agricultural productionB.To explain how demand for a product determines its costC.To describe how domestic shortages are createdD.To illustrate the concept of absolute advantage3.According to the professor,what indicates that a country has an absolute advantage in trade?A.It can produce an item more efficiently than other countries.B.It is wealthy enough to import everything that it needs.C.It consistently exports more than it imports.D.It does not have to import any goods from other countries.4.The professor gives an example of two countries that produce televisions and chairs. What does she predict will happen if the economic decisions of both countries are based on the principle of comparative advantage?[Click on2answers.]A.The prices of televisions and chairs will go down in both countries.B.More chairs and televisions will be manufactured in each country.C.Imports of televisions and chairs will decrease in each country.D.The total supply of televisions and chairs will increase in both countries.5.Why does the professor talk about going to the movies?A.To demonstrate the difference between absolute and comparative advantageB.To provide an example to help explain the concept of opportunity costsC.To illustrate the advantages of specialization in the entertainment industryD.To show that economic theories do not always apply on a personal level6.Why does the professor say this:say we have two countries and say they each make only two products and they trade only with each other.Simplistic I know.But well,you'll see where I'm going with this in a moment.A.To reassure the students that the example will help illustrate her pointB.To apologize to the students for using an example that is difficult to understandC.To prepare the class for a shift to a new topicD.To return to a point she made earlier答案C D A AD B A译文请听经济学课上的部分内容。

托福听力tpo51lecture1、2、3、4原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (3)答案 (5)译文 (6)Lecture2 (7)原文 (7)题目 (10)答案 (12)译文 (12)Lecture3 (14)原文 (14)题目 (16)答案 (18)译文 (18)Lecture4 (20)原文 (20)题目 (22)答案 (24)译文 (24)Lecture1原文NARRATOR:Listen to part of a lecture in a botany class.FEMALE PROFESSOR:So,continuing with crop domestication,and corn—or,um, maize,as it's often called.Obviously it's one of the world's most important cropstoday.It's such a big part of the diet in so many countries,and it's got so many different uses,that it's hard to imagine a world without it.But because it doesn't grow naturally,without human cultivation,and because there's no obvious wild relative of maize…uh,well,for the longest time,researchers weren’t able to find any clear link between maize and other living plants.And that's made it hard for them to trace the history of maize.Now,scientific theories about the origins of maize first started coming out in the 1930s.One involved a plant called teosinte.Teosinte is a tall grass that grows wild in certain parts of Mexico and Guatemala.When researchers first started looking at wild teosinte plants,they thought there was a chance that the two plants—um, maize and teosinte—were related.The young wild teosinte plant looks a lot like the corn plant,and the plants continue to resemble each other—at least superficially—even when they're developed.But when the scientists examined the fruits of the two plants,it was a different story. When you look at ripe corn,you see row upon row of juicy kernels…um,all those tiny little yellow squares that people eat.Fully grown teosinte,on the other hand, has a skinny stalk that holds only a dozen or so kernels behind a hard,um,almost stonelike casing.In fact,based on the appearance of its fruit,teosinte was initially considered to be a closer relative to rice than to maize.But there was one geneticist,named George Beadle,who didn't give up so easily on the idea that teosinte might be…well…the“parent”of corn.While still a student in the1930s,Beadle actually found that the two plants had very similar chromosomes—very similar genetic information.In fact,he was even able to make fertile hybrids between the two plants.In hybridization,you remember,the genes of two species of plants are mixed to produce a new,third plant—a hybrid.And if this offspring—this hybrid—is fertile,then that suggests that the two species are closely related genetically.This new,hybrid plant looked like an intermediate,right between maize and teosinte.So,Beadle concluded that maize must've been developed over many years,uh,that it is a domesticated form of teosinte.Many experts in thescientific community,however,remained unconvinced by his conclusions.They believed that,with so many apparent differences between the two plants,it would have been unlikely that ancient—that prehistoric peoples could’ve domesticated maize from teosinte.I mean,when you think about it,these people lived in small groups,and they had to be on the move constantly as the seasons changed.So for them to selectively breed,to have the patience to be able to pick out just the right plants…and gradually—over generations—separate out the durable,nutritious maize plant from the brittle teosinte that easily broke apart…it's a pretty impressive feat,and you can easily see why so many experts would have been skeptical.But,as it turns out,Beadle found even more evidence for his theory when he continued his experiments,producing new hybrids,to investigate the genetic relationship between teosinte and maize.Through these successive experiments,he calculated that only about five specific genes were responsible for the main differences between teosinte and maize—the plants were otherwise surprisingly similar genetically.And more recently,botanists have used modern DNA testing to scan plant samples collected from throughout the Western Hemisphere.This has allowed them to pinpoint where the domestication of maize most likely took place—and their research took them to a particular river valley in southern Mexico.They've also been able to estimate that the domestication of maize most likely occurred about9,000 years ago.And subsequent archaeological digs have confirmed this estimate.In one site,archaeologists uncovered a set of tools that were nearly9,000years old.And these tools were covered with a dusty residue…a residue of maize,as it turns out…thus making them the oldest physical evidence of maize that we've found so far.题目1.What is the lecture mainly about?A.A research study that compares wild and domesticated plantsB.Problems with a commonly held hypothesis about the origin of teosinteC.Reasons why wild plants are usually unsuitable for agricultureD.The process used to identify the ancestor of a modern crop2.What evidence seemed to indicate that maize and teosinte are not related?A.Young teosinte plants do not physically resemble young maize plants.B.Preliminary DNA evidence indicated that teosinte was related to rice.C.Maize and teosinte usually grow in significantly different climates.D.Maize and teosinte have very different types of kernels.3.Why does the professor discuss hybrids?A.To explain how a geneticist confirmed that maize was widely grown9,000years agoB.To indicate the earliest method used by geneticists to identify plant originsC.To explain a method used to demonstrate a link between two plant speciesD.To describe how geneticists distinguish between wild plants and domesticated plants4.What was most researchers'initial view of George Beadle's theory about teosinte?A.They accepted it but questioned the evidence cited.B.They rejected it because of conflicting archaeological evidence.C.They questioned it because it implies that ancient farmers were sophisticatedplant breeders.D.They questioned it because genetic research was viewed with skepticism at that time.5.What did Beadle conclude about maize and teosinte?A.Both plants lack particular genes that are common in most domesticated plants.B.Both plants have particular genes that enable them to adapt to varying climates.C.Only a small number of genes are responsible for the differences between the two plants.D.The genetic composition of both plants is very similar to that of rice.6.According to the professor,why was the discovery of stone tools important?A.It proved that teosinte was simultaneously domesticated in multiple locations.B.It helped to confirm the period in which maize was first domesticated.C.It suggested that maize required farming techniques that were more complex than experts had previously assumed.D.It provided evidence that maize plants were used for more purposes than experts had previously assumed.答案D D C C C B译文旁白：请听一段植物学讲座的节选。

托福听力tpo67lecture1、2、3原文+题目+答案+译文Lecture1 (2)原文 (2)题目 (4)答案 (6)译文 (6)Lecture2 (7)原文 (7)题目 (10)答案 (12)译文 (12)Lecture3 (13)原文 (14)题目 (16)答案 (18)译文 (18)Lecture1原文Professor:Now we've said that animal behavior patterns involve an interplay between an animal and its environment.In particular,behavior patterns can change as an animal becomes adapted to its environment.We can see the results of this in the way that animals have developed different types of feeding behavior.Animals are generally classified as a generalist feeders and specialist feeders.Now,um,these terms are used in a variety of ways.At times,they're used to refer to an animal's range of habitats.I've also seen them used to describe the number of foraging techniques that are used by an individual or species.Um,but for our purposes,we're going to use them to refer to the range of food items that are eaten by a species.So a generalist feeder is a species that eats a wide variety of foods during its lifetime.And a specialist is a species that feeds on a highly restricted number of foods.A good example of a generalist would be a rat.Rats are notorious for eating just about anything that's available,whether it's a plant or an animal.At the other end of the spectrum,we have the koala which eats only the leaves of eucalyptus trees.Okay,now there are advantages to each.For a generalist,If1type of food isn't around,it can feed on another that's more abundant.On the other hand,the advantage of being a specialist is that the animal is well adapted to its food.You could say that specialists are feeding masters,their consumption,even their digestive system is just so finely tuned.For instance,take the koala.The eucalyptus leaves that it feeds on,don't contain much protein.What's more,the leaves contain compounds that are poisonous to most species?But the koalas digestive system has adapted to handle this.It's liver deactivates,the poisonous compounds,and its digestive system is designed to extract the maximum amount of nutrients from the leaves.So it's not a question of which strategy is better.The real question is,what determines how selective animal species are in what they eat?Well,the answer maylie in a concept called optimal foraging.The idea is that natural selection favors animals whose feeding behavior has the lowest cost to benefit ratio.That is you want to get the best healthiest food you can.And you want to do it as quickly as possible. And as easily as possible.Now,in a natural environment,no animal forage in an absolutely optimal manner. But,well,I read some research on a little rat called the kangaroo rat,which lives in deserts in North America.The kangaroo rat is a generalist which eats plant matter like seeds and fruit.It lives in deep burrows which provide protection from the desert heat and from predators like hawks or snakes.And it goes foraging at night for food.For plant matter,under the protection of darkness,even though it's a generalist.If the only thing available is seed,if a choice of seeds is available to it,it picks up seeds that provide more energy than those it leaves behind.And it carries them back to its burrow.Once it's there,it might eat only the richest seeds from the ones that brought back.So it selects seeds outside in a way that lets it spend as little time as possible foraging in that risky environment,and then sorts out its food later when it's safely in its burrow.Oh,yes,Kenneth.You have a question?Male student:But what about the koala?It gets by uh,by being even more selective, you'd think you would be really risky to rely completely on eucalyptus leaves. Wouldn't it be better to diversify like the kangaroo rat,and eat,at least one or two other things?Professor:Well,what do you think the koala would say?What do I gain by being so selective?In terms of optimal foraging,it's clear that eucalyptus trees provide an abundant source of food.Other animals can't eat the leaves and think of how little energy the koala uses.It spends only about3hours each day eating to get the energy it needs.So being a specialist allows it to get the nutrients it needs with minimal expenditure of energy.题目1.What is the lecture mainly about?A.The reasons why some animals eat only plantsB.The advantages of two different feeding adaptationsC.The variety of foods that certain animals can eatD.The relationship between two animals that share a habitat2.What definition of the term“generalist”does the professor use in the lecture?A.An animal species that eats a wide variety of foodsB.An animal species that lives in a range of different habitatsC.An animal species that uses several techniques to forage for foodD.An animal species that forages at several different times of the day3.What points does the professor make about the koala’s specialist feeding habits? [Click on2answers.]A.It obtains all the food it needs in relatively little time.B.It requires large amounts of protein in its diet.C.It can eat leaves that are poisonous to other animals.D.It spends most of its time eating.4.What does the professor imply about the kangaroo rat?A.It will take more risks when foraging for high-energy food.B.It is one of the most selective feeders in North America.C.Its competitors often eat its food supply.D.It is selective when choosing what food it eats.5.How does the professor organize the information in the lecture?A.By contrasting an old theory with a new theoryB.By defining important terms and then giving examples of themC.By describing the similarities between two animalsD.By describing a problem and then suggesting some solutions6.Why does the professor say this:Male student:But what about the koala?It gets by uh,by being even more selective, you'd think you would be really risky to rely completely on eucalyptus leaves. Wouldn't it be better to diversify like the kangaroo rat,and eat,at least one or two other things?Professor:Well,what do you think the koala would say?What do I gain by being so selective?In terms of optimal foraging,it's clear that eucalyptus trees provide an abundant source of food.Other animals can't eat the leaves and think of how little energy the koala uses.A.To express agreement that the koala should eat a greater variety of foodB.To indicate that the koala’s behavior does not illustrate optimal foragingC.To remind the man of the characteristics of selective feedersD.To encourage the man to consider the koala’s feeding behavior differently答案B A ACD B D译文我们已经说过动物的行为模式涉及到动物和它的环境之间的相互作用。

托福听力tpo60 lecture1、2、3 原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (3)答案 (5)译文 (5)Lecture2 (7)原文 (7)题目 (9)答案 (11)译文 (12)Lecture3 (13)原文 (13)题目 (16)答案 (18)译文 (18)Lecture1原文Listen to part of a lecture in an art history class.As you know, artists today can choose from an enormous selection of media, including water colors, acrylic paints, not to mention special pains formulated for almost any surface you might wanna paint on. But even so, oil paints are still the medium of choice among most professional artists and hobbyists. So why is that? well, for one thing, oil paints extremely versatile, suitable for many different painting styles, different subjects, and different sizes of work. Another advantage is thatthey're easy to use. Even for beginners, they can be manipulated. You can apply oil paint to a canvas. And then because they don't dry right away, they can be scraped off and paint it over.So you don't have to waste expensive material every time you make a change. Unlike acrylic paint, which really can't be moved once it's applied, acrylic paints dry very quickly. So in general, when using them, it's more difficult to make changes. And with watercolors, you can't really paint over a mistake, because it really diminishes the freshness of the colors. So oil paint is the medium of choice for many painters. Nowadays, anyway, in terms of art history, oil paints actually pretty young in Europe before the invention, rather, the development of oil paint, painters mostly used Tempera. Tempera was made with egg yolk. Believe it or not, the yoke acted as a binder. A binder enables the color pigment to stick to your canvas, and no temporal wasn't always yellow. If that's what you're thinking. Artists made their own paint by mixing egg yolk with a color pigment like powdered iron ore copper. But it dried very fast, which left little room for error or change.You really had to get it right the first time. Then in the early 15th century, a Flemish painter named Jan of Van Eyck started experimenting up after that emperor in one of the Nikes paintings cracked while drawing in the sun. He decided to try to make a paint that would avoid this fate. So he tried. And oil mixture, actually other painters before him had tried using oils as a binder. So while the Nikes credited with inventing oil paint, it's not entirely true. In Greece and Italy, olive oil had been used to prepare pigment mixtures, but the paint took a really long time to dry, just the opposite of tempera. But van Eyck had a secret recipe for his oil paint. He used linseed oil. Not only did this paint dry without cracking, van dyke also discovered that it could be applied in very thin layers. This technique gave the colors of depth that was previously unknown. And just as important, the linseed oil actually increased the brilliance of the color. So as a result, pigment oil mixtures became very popular among artists. Some tried to improve the paint by developing their own recipes, like uh, by using walnut oil, for instance, or by cooking their oil mixtures. But a greatmany began using some sort of oil as their binder.Now with all this experimentation with mixtures, well, it took a long time for artists to get comfortable with using these new oil paints to get a true feeling for how to apply them to the best effect. The early painters in oil like that Ike laid the paint down in thin layers with brush strokes that were so delicate that they're practically invisible. And it really wasn't until the end of the 16th century and in the 17th century that the full potential of oil paint was realized, for example, that's when artists finally began to combine delicately painted areas with thick brush strokes. So you could actually see the marks of the brush combining the rough and the smooth gives oil paintings great textural depth. Of course, the public who are used to smooth surfaces actually complained that these paintings looked unfinished. And some of that attitude carried over until later centuries, like, well, you're probably familiar with the work of the painter Vincent Van Gogh. Van gogh's famous nowadays for his thick, swirling brush strokes. But amazingly enough, his work was not appreciated back in the 19th century, and he sold just one painting during his lifetime. Of course, the French impressionists, who were his contemporaries, attained more popular acclaim, but they used a different technique. They applied oil paint and thick dabbs to depict the effects of light on the landscape.题目1.What does the professor mainly discuss?A. The relationship between painting techniques and types of paint that are usedB. Reasons for the changes in the popularity of oil paint since the seventeenth centuryC. The historical development and use of oil paintD. The main differences between oil paint and tempera2.What reasons does the professor give for the popularity of oil paint among modern artists?[Click on 2 answers.]A. It can be used for a number of painting styles.B. It allows artists to make changes.C. It does not fade easily.D. It can be made easily even by amateur painters.3.What property do tempera and acrylic paint have in common?A. They do not stick well to the canvas.B. They tend to crack as they dry.C. They tend to make colors look dull.D. They dry very quickly.4.What are two points the professor makes about the painter Jan van Eyck?[Click on 2 answers.]A. He did not invent the use of oil as a binder.B. He improved his own oil mixtures by heating them.C. He invented tempera.D. He applied oil paint to a canvas in thin layers.5.Why does the professor talk about combining delicate brushstrokes with thickbrushstrokes?A. To explain the popularity of van Eyck's paintingsB. To describe a difference between linseed oil and olive oil as a binderC. To indicate that artists became more experienced in the use of oil paintD. To point out a similarity between the painters van Eyck and van Gogh6.Why does the professor mention Vincent van Gogh?A. To emphasize that paintings made with thick brushstrokes were unpopular in the pastB. To show that artists did not know how to use oil paints correctly until the nineteenth centuryC. To describe the origin of a painting technique used by the French ImpressionistsD. To support his statement about when painters first began to use thick brushstrokes答案C ABD AD C A译文请听艺术史课上的部分内容。

托福听力tpo49lecture1、2、3、4原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (4)答案 (6)译文 (6)Lecture2 (8)原文 (8)题目 (10)答案 (12)译文 (12)Lecture3 (14)原文 (14)题目 (17)答案 (19)译文 (19)Lecture4 (21)原文 (21)题目 (23)答案 (25)译文 (25)Lecture1原文NARRATOR:Listen to part of a lecture in a geology class.MALE PROFESSOR:Alaska is fascinating to geologists because of its incrediblelandscapes.Uh,permafrost has a lot to do with this.That is,the areas where the ground—the soil—is always frozen,except for the very top layer—what we call the active layer of permafrost—which melts in the summer and refreezes again in the winter.The northern part of Alaska is covered in lakes—thousands of them—and most of these are what we call thaw lakes.T-h-a-w.Thaw lakes.I'm gonna show you a few sketches of them in a minute,so you'll have a good idea of what I'm talking about.So, how these thaw lakes are formed has to do with…OK,it starts with ice wedges.The top part of the ice wedge melts—Should I back up?Ice wedges form when water runs into cracks in the ground,the permafrost,then freezes.You ever see mud after it dries?Dried mud has cracks,because when it dries, it contracts,it shrinks.Well,in winter,permafrost behaves similarly.It shrinks in winter,because it freezes even more thoroughly then,and as it shrinks,it forms deep,deep cracks.Then in the summer,when the active layer—the top layer of the permafrost—melts,the melt water runs into those cracks in the permafrost,then freezes again—because that ground,the ground beneath the active layer,is still below freezing.So,you have wedges of ice in the permafrost.Now the ice wedges widen the original cracks in the permafrost,because water expands when it freezes.All right?OK,then in autumn,the active layer on top freezes again.Then in winter,the permafrost starts contracting again and the cracks open up even wider.So the next summer,when the active layer melts again and flows into the widened cracks…and…freezes…it makes the cracks even wider.So it’s sort of a cycle through which the cracks and the wedges grow wider and wider.So when the ice wedge reaches a certain size,its top part—in the active layer—turns into a little pond when it melts in the summer.And that's the beginning of your thaw lake.[pause]There are thousands of them in northern Alaska.One of the most fascinating things about these lakes—and this is important—is that they mostly havethe same shape.Like an elongated oval,or egg shape.And what's more,all the ovals are oriented in the same way.Here's an idea of what they look like,what the landscape looks like from an aerial view,with the lakes side by side.There's been considerable research done to try to figure out what causes them to be shaped and oriented this way.We know that the shape and orientation are caused by the way the lakes grow once they're formed,but the question is,what makes them grow this way?One theory sees winds as the cause.This region of Alaska has strong winds that blow perpendicular to the lakes.What happens is,wind blows straight into the longer side of the lakes.Now,wouldn’t that erode the lake bank in that direction?The same direction as the wind?Well…no.Actually,what happens is that the waves caused by the winds build a sorta protective layer of sediment—it's called a“protective shelf”—along the bank of the lake directly in front of them;so that bank is shielded from erosion,and the waves are diverted to the sides,to the left and to the right,and that’s why the left and the right banks start eroding.Get it?The bank straight ahead is protected,but the lake currents--the waves--erode the banks to the sides.That's the current model,um,the wind erosion model,which is generally accepted.But,there's a new theory that says that[deliberately]thaw slumping,not wind,is what shapes the thaw lakes.Thaw slumping,um…OK.Sometimes,in the summer,the temperature rises pretty quickly.So the active layer of permafrost thaws faster than the water can drain from the soil.So the sides of the thaw lakes get,like,mushy,and slump,or slide,into the lake.Then,the lake water spreads out more,and the lake gets bigger,OK?Also,in that part of Alaska,the terrain is gently sloped,so the lakes are all on an incline.Here.Now,this is an exaggeration of the angle—the hill isn't this steep—butsee how with the lake's banks,the side that is farther downhill…it's smaller,lower. This short bank thaws faster than the tall one does,so it falls into the lake—it slumps, much more and much faster than the other bank.When the short banks of many lakes slump,they move farther downhill and the lakes grow—all in the same downhill direction.This is a new theory,so it hasn't been tested much yet.In field studies,when we've looked at the banks of these thaw lakes,there's not much evidence of slumping. We'd expect to see cliff-like formations there,from the slumping,but we haven't really found many of those.题目1.What is the main purpose of the lecture?[Click on two answers.]A.To contrast how different kinds of thaw lakes growB.To explain why a new theory of thaw lakes is gaining acceptanceC.To explain how processes in permafrost lead to the formation of thaw lakesD.To describe two competing theories about the growth of thaw lakes2.The professor explains thaw lake formation as a cycle of events that occur repeatedly.Summarize this cycle,starting with the event filled in below.[Click on a sentence.Then drag it to the space where it belongs.The first one is done for you. One sentence will not be used]A.Meltwater flows into cracks in permafrostB.Ice wedges inside permafrost completely meltC.Freezing water expands cracks in permafrostD.Ice in the active layer melts as temperatures riseE.Permafrost shrinks and cracks as temperatures drop..3.What is the significance of the'protective shelf'discussed by the professor?A.It prevents the slumping of lake banks.B.It shields the lake surface from strong winds.C.It redirects the waves to lake banks that do not face the wind.D.It allows the lakes to grow in the same direction as the wind blows.4.According to the thaw slumping model,which side of a thaw lake grows fastest?A.The side where the bank is shortestB.The side least exposed to windC.The side that is at the highest elevationD.The side opposite the protective shelf5.What is the professor's opinion of the thaw slumping model?A.He thinks it was urgently needed.B.He is not convinced that it has a firm basis.C.He thinks it would be better if it were simplified.D.He does not think it is very different from the old model.6.Why does the professor say this:You ever see mud after it dries?A.He wants some information from the students.B.He thinks that the students may find an example helpful.C.He realizes that he forgot to mention an important topic.D.He wants to point out an important difference between frozen ground and dry ground.答案CD EDACB C A B B译文听一段地质学的讲座。