【托福听力备考】TPO3听力文本——Lecture 4
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【托福听力备考】TPO3听力文本——Lecture 1对于很多学生来说,托福TPO材料是备考托福听力最好的材料。
相信众多备考托福的同学也一直在练习这套材料,那么在以下内容中我们就为大家带来托福TPO听力练习的文本,希望能为大家的备考带来帮助。
Lecture 1 Environmental scienceNarrator:Listen to part of a lecture in an environmental science class.Now, we’ve been talking about the loss of animal habitat from housingdevelopments, um…, growing cities – small habitat losses. But today I wannabegin talking about what happens when habitat is reduced across a large area.There are, of course, animal species that require large areas of habitat, andsome migrate over very long distances. So what’s the impact of habitat loss onthose animals – animals that need large areas of habitat?Well, I’ll use the humming birds as an example.Now you know a humming bird is amazingly small, but even though it’s reallytiny, it migrates over very long distances, travels up and down the westernhemisphere – the Americas, back and forth between where it breeds in the summerand the warmer climates where it spends the winter. So we would say that thiswhole area over which it migrates is its habitat because on this long-distancejourney, it needs to come down to feed and sleep every so often, right?Well, the humming bird beats its wings – get this – about 3 thousand timesper minute. So you think, wow, it must need a lot of energy, a lot of food,right? Well, it does. It drinks a lot of nectar from flowers and feeds on someinsects, but it’s energy-efficient too. You can’t say it isn’t. I mean, asitflies all the way across the Gulf of Mexico, it uses up almost none of its bodyfat. But that doesn’t mean it doesn’t need to eat. So humming birds have to relyon plants in their natural habitat.And it goes without saying, but, well, the opposite is true as well, plants depend on humming birds too. There are some flowers that can only be pollinated by the humming birds. Without it stopping to feed and spreading pollen from flower to flower, these plants would cease to exist.But the problem, well, as natural habitat along these migration routes is developed by humans for housing or agriculture or cleared for raising cattle, for instance, there is less food available for migrating humming birds. Their nesting sites are affected too, the same, by the same sorts of human activities.And all of these activities pose a real threat to the humming birdpopulation.So to help them survive, we need to preserve their habitats. And one of the concrete ways people have been doing this is by cleaning up polluted habitat areas and then replanting flowers, um, replanting native flowers that humming birds feed on.Promoting ecological tourism is another way to help save their habitat. As the number of visitors, eco-tourists who come to humming bird habitats to watch the birds, the more the number of visitors grows, the more local businessesprofit, so ecological tourism can bring financial rewards, all the more reason to value these beautiful little creatures in their habitat, right?But to understand more about how to protect and support humming birds the best we can, we’ve got to learn more about their breeding, nesting sites and migration routes, and also about the natural habitats we find there. That should help us determine how to prevent further decline in the population.A good research method, a good way to learn more, is by running a banding study. Banding the birds allows us to track them over their lifetime. It’s been a practice that’s been used by researchers for years. In fact, most of what we know about humming birds comes from banding studies, where we capture a humming bird and make sure all the information about it, like its weight and age and length, are all recorded, put into international, an international information database. And then we place an extremely lightweight band on one of its legs, well, what looks like a leg, although technically it’s considered part of the bird’s foot.Anyway, these bands are perfectly safe, and some humming birds have worn them for years with no evidence of any problems. The band is labeled with a tracking number, oh, and there is a phone number on the band for people to call for free, to report a banded bird they’ve found or recaptured. So when a banded bird is recaptured and reported, we learn about its migration route, its growth, and how long it has been alive, its lifespan. One recaptured bird had been banded almost 12 years earlier – she is one of the oldest humming birds on record.Another interesting thing we’ve learned is that some humming birds, um, they no longer use a certain route. They travel by a different route to reach their destination. And findings like these have been of interest to biologists and environmental scientists in a number of countries who are trying to understand the complexities of how changes in a habitat affect the species in it.。
【托福听力备考】TPO3听力文本——Lecture 2对于很多学生来说,托福TPO材料是备考托福听力最好的材料。
相信众多备考托福的同学也一直在练习这套材料,那么在以下内容中我们就为大家带来托福TPO听力练习的文本,希望能为大家的备考带来帮助。
Lecture 2 Film historyNarrator:Listen to part of a lecture in a film history class.Professor:Okay, we’ve been discussing films in the 1920s and 30s, and how back then film categories, as we know them today, had not yet been established. We said that by today’s standards, many of the films of the 20s and 30s would be considered hybrids, that is, a mixture of styles that wouldn’t exactly fit into any of today’s categories. And in that context, today we are going to talk about a film-maker who began making very unique films in the late 1920s. He was French, and his name was Jean Painlevé.Jean Painlevé was born in 1902. He made his first film in 1928. Now in a way, Painlevé’s films conform to norms of the 20s and 30s, that is, they don’t fit very neatly into the categories we use to classify films today. That said, even by the standards of the 20s and 30s, Painlevé’s films were a unique hybrid of styles. He had a special way of fusing, or some people might say, confusing, science and fiction. His films begin with facts, but then they become more and more fictional. They gradually add more and more fictional elements. In fact, Painlevé was known for saying that science is fiction.Painlevé was a pioneer in underwater film-making, and a lot of his short films focused on the aquatic animal world. He liked to show small underwater creatures, displaying what seemed like familiar human characteristics – what we think of as unique to humans. He might take a clip of a mollusk going up and down in the water and set it to music. You know, to make it look as if the mollusk were dancing to the music like a human being – that sort of thing. But then he suddenly changed the image or narration to remind us how different the animals are, how unlike humans.He confused his audience in the way he portrayed the animals he filmed, mixing up our notions of the categories human and animal. The films make us a little uncomfortable at times because we are uncertain about what we are seeing. It gives him films an uncanny feature: the familiar made unfamiliar, the normal made suspicious. He liked twists, he liked the unusual. In fact, one of his favorite sea animals was the seahorse because with seahorses, it’s the male that carries the eggs, and he thought that was great. His first and most celebrated underwater film is about the seahorse.Susan, you have a question?Student 1:But underwater film-making wasn’t that unusual, was it? I mean, weren’t there other people making movies underwater?Professor:Well, actually, it was pretty rare at that time. I mean, we are talking the early 1930s here.Student 1:But what about Jacques Cousteau? Was he like an innovator, you know, with underwater photography too?Professor: Ah, Jacques Cousteau. Well, Painlevé and Cousteau did both film underwater, and they were both innovators, so you are right in that sense. But that’s pretty much where the similarities end.First of all, Painlevé was about 20 years ahead of Cousteau. And Cousteau’s adventures were high-tech, with lots of fancy equipment, whereas Painlevé kind of patchedequipment together as he needed it. Cousteau usually filmed large animals, usually in the open sea, whereas Painlevé generally filmed smaller animals, and he liked to film in shallow water.Uh, what else? Oh well, the main difference was that Cousteau simply investigated and presented the facts – he didn’t mix in fiction. He was a strict documentarist. He set the standard really for the nature documentary. Painlevé, on the other hand, as we said before, mixed in elements of fiction. And his films are much more artistic, incorporating music as an important element.John, you have a question?Student 2:Well, maybe I shouldn’t be asking this, but if Painlevé’s films are so special, so good, why haven’t we ever heard of them? I mean, everyone’s heard of Jacques Cousteau.Professor: Well, that’s a fair question. Uh, the short answer is that Painlev é’s style just never caught on with the general public. I mean, it probably goes back at least in part to what we mentioned earlier, that people didn’t know what to make of his films – they were confused by them, whereas Cousteau’s documentaries were very straightforward, met people’s expectations more than Painlevé’s films did. But you true film history buffs know about him. And Painlevé is still highly respected in many circles.。
2020年3月26日托福听力答案解析托福听力Conversation 1女生刚刚成为outdoor workshop的新晋会长,然后老师恭喜她,她就跟老师说没有收到邮件,然后希望你能当我们leader,老师说你自己当就挺好的。
然后就想让这个教授做她的导师,因为她没做过leader就很紧张(有题)。
然后又说举行活动的一个地方被占了,反正吹了就问B—能够吗?professor就说挺好啊,是outdoor的活动呀,教授还说能够搞一些introductory的活动,还能够培养collaboration定下以后活动的基调,然后这个女生说自己活动的计划之类之类(这里有题),教授听了说你这不是想的很好吗?而且我有一个学生说能够为你的社团提供fund。
托福听力Lecture 1[人类学]讲英国的巨石阵Stone Henge和距离它不远的Durrington Wall, 巨石阵是石头做的,两圈,而那个Wall是木炭/木材建的(石头永久,木头不永久,推测可能有象征意义,有题),里面发现了一些动物尸骨和Pottery,两个地方都有path到河边。
所以推测他们先到Durrington Wall吃大餐feast, 然后去河边,再去巨石阵祭祀(有题考顺序)。
托福听力Lecture 2[考古学]Ice Age后有一段特殊气温降低时期使大型动物消失,科学家发现了一层PBD? 大概是一层glacier,下面有大型动物化石而上面没有,所以推测这可能是一个原因。
然后另一个可能是陨石原因,提到恐龙灭绝是因为陨石撞地球。
然后这层PBD中含有很多nano颗粒,以及一种化学微颗粒,考虑源于meter dust。
但是房顶上也有这种化学微颗粒,所以不能完全推断大型动物灭绝的原因。
托福听力Conversation 2学生改了topic题目(主旨题),一开始topic是古代北非burberry地区相关,但是因为时间太久远几乎找不到什么资料,教授推荐了个网址去搜资料。
【托福听力备考】TPO3听力文本——Lecture 3众所周知,托福TPO材料是备考托福听力最好的材料。
相信众多备考托福的同学也一直在练习这套材料,那么在以下内容中我们就为大家带来托福TPO听力练习的文本,希望能为大家的备考带来帮助。
Lecture 3 Art HistoryNarrator:Listen to part of a lecture in an Art History class. The professor has been discussing the origins of art.ProfessorSome of the world’s oldest preserved art is the cave art of Europe, most of it in Spain and France. And the earliest cave paintings found to date are those of the Chauvet Cave in France discovered in 1994.And you know, I remember when I heard about the results of the dating of the Chauvet paintings, I said to my wife, “Can you believe these paintings are over 30,000 years old?”And my 3-year-old daughter piped up and said, “Is that older than my great-grandmother?” That was the oldest age she knew. And you know, come to think of it. It’s pretty hard for me to really understand how long 30,000 years is too.I mean, we tend to think that people who lived at that time must have been pretty primitive. But I’m gonna show you some slides in a few minutes and I think you will agree with me that this art is anything but primitive. They are masterpieces. And they look so real, so alive that it’s very hard to imagine that they are so very old.Now, not everyone agrees on exactly how old. A number of the Chauvet paintings have been dated by a lab to 30,000 or more years ago. That would make them not just older than any other cave art, but about twice as old as the art in the caves at Altamira or Lascaux, which you may have heard of. Some people find it hard to believe Chauvet is so much older than Altamira and Lascaux, and they noted that only one lab did the dating for Chauvet, without independent confirmation from any other lab. But be that as it may, whatever the exact date, whether it’s 15,000, 20,000 or 30,000 years ago, the Chauvet paintings are from the dawn of art. So they are a good place to start our discussion of cave painting.Now, one thing you’ve got to remember is the context of these paintings. Paleolithic humans - that’s the period we are talking about here, the Paleolithic, the early stone age, not too long after humans first arrived in Europe - the climate was significantly colder then, and so rock shelters, shallow caves were valued as homes protected from the wind and rain. And in some cases at least, artists drew onthe walls of their homes.But many of the truly great cave art sites like Chauvet were never inhabited. These paintings were made deep inside a dark cave, where no natural light can penetrate. There’s no evidence of people ever living here. Cave bears, yes, but not humans. You would have had to make a special trip into the cave to make the paintings, and a special trip to go see it. And each time you’d have to bring along torches to light your way. And people did go see the art. There’s charcoal marks from their torches on the cave walls clearly dating from thousands of years after the paintings were made. So we can tell people went there. They came but they didn’t stay. Deep inside a cave like that is not really a place you’d want to stay, so, why? What inspired the Paleolithic artists to make such beautiful art in such inaccessible places? We’ll never really know of course, though it’s interesting to speculate.But, um, getting to the paintings themselves, virtually all Paleolithic cave art represents animals, and Chauvet is no exception. The artists were highly skilled at using, or even enhancing, the natural shape of the cave walls to give depth and perspectives to their drawings, the sense of motion and vitality in these animals. Well, wait till I show you the slides. Anyway, most Paleolithic cave art depicts large herbivores. Horses are most common overall with deer and bison pretty common too, probably animals they hunted.But earlier at Chauvet, there is a significant interest in large dangerous animals, lots of rhinoceros, lions, mammoth, bears. Remember that the ranges of many animal species were different back then, so all these animals actually lived in the region at that time.But the Chauvet artists didn’t paint people. There is a half-man-half-bison creature and there is outlines of human hands but no depiction of a full human.So, why these precise animals? Why not birds, fish, snakes? Was it for their religion, magic or sheer beauty? We don’t know. But whatever it was, it was worth it to them to spend hours deep inside a cave with just a torch between them and utter darkness. So, on that note, let’s dim the lights, so we can see these slides and actually look at the techniques they used.。
托福听力学习笔记之TPO3:lecture4下面就让小编来为大家介绍一下这篇托福听力TPO3学习笔记的内容吧,这是小编的一些见解,以便帮助大家更加充分的理解TPO真题,希望能够给正在准备托福听力的考友们带来帮助。
一、难词注解spectrum n. 光谱;频谱;范围;余象radiation n. 辐射;发光;放射物pattern n. 模式;图案;样品composition n. 作文,作曲,作品;[材] 构成;合成物;成分makeup n. 化妆品;组成;补充;补考spectrograph n. 光谱仪;摄谱仪二、长难句分析This process was repeated over and over again for many different elements, so we can figure out the chemical makeup of another star by comparing the spectral pattern it has to the pattern of the elements in the library.而很多元素都会经历这样的过程,循环往复。
这样我们就可以通过将某元素的光谱图案和光谱合集中的光谱图案进行比较,我们可以获得其他行星的化学成分。
难词释义:repeated v. 重复;复述(repeat的过去分词)elements n.自然力量份子要素难句类型:by伴随状语,定语从句难句拆分:by comparing 通过比较it has to the pattern of the elements in the library从句修饰前面的spectral pattern三、考题对应考点12.强调原则,Spectroscopy is basically the study of spectra and spectral lines of light…It makes it possible to analyze the light emitted from stars. When you analyze this light, you can figure out their distance from the earth, and identify what they are made of, determine their chemical composition.”虽然是先提的是spectroscopy,但是目的是想通过此进行化学元素的识别。
2020年3月13日托福听力答案解析3月13日托福听力Conversation 1学生去见考古学老师问关于他的论文选题,他对加拿大的某个遗址感兴趣。
后面提到了大遗址和小遗址,大遗址包括的信息很多,例如手工制品等等。
小遗址信息少,但是累加起来也会有很多信息。
老师认为不应该忽略小遗址。
-TPO部分对应参考 (学术话题类TPO10-C1/T19-C1)3月13日托福听力Lecture 1艺术课堂讲了一种participate art. 有个艺术家名字缩写是PMJ。
后来大家拿着key 去unlock (这里有题)然后提到了人面对面不说话看着对方,有energy exchange。
然后提到一个test, 就是人会在一起做一些事情,会在纸上写东西等等。
还提到这个很少被作为美术题TK,但是应用到了音乐里面。
-TPO部分对应参考(艺术类TPO3-L3/TPO16-L4)3月13日托福听力Lecture 2讲到关于某种飞行器,由达芬奇参照鸟类飞行提出,翅膀上下煽动的形式。
但是后来有个人说人的肌肉不可能由充足的力量来飞起来。
但是这并不能防碍人们继续研究这种飞行器。
他们开始寻找动力来支持飞行,这种持续了很久,都没有成功。
老师认为有时这种模仿会negative。
后来提到滑翔方式和莱特兄弟的飞机。
题目里说到geese.-TPO部分对应参考 (科学类TPO3-L1/TPO11-L3)3月13日托福听力Conversation 2学校学生去见Dean, 建议学校应该提供学校的信息来协助新生。
Dean说网站上有信息了,学生说那些信息不好找。
Dean问了她这会有什么协助,她说她的advisor帮了她很多。
建一个网站仅仅她的部分计划,人与人面谈比较好。
Dean 说没钱支持,学生说不要紧,只用提供办公室和打印费就行了,员工都是志愿者。
然后dean说能够,但是还是要向学校 propose.-TPO部分对应参考 (校园场景类TP8-C1/T23-C1)3月13日托福听力Lecture 3Environment biology 课堂,关于濒临灭绝的生物的保护和所带来的影响。
智 课 网 托 福 备 考 资 料托福听力TPO3学习笔记之lecture3-智课教育旗下智课教育以下是小编在学习托福听力TPO3中的lecture3时做的学习笔记,针对难词注解、长难句分析以及考题对应考点这三大方面展开,仅供参考。
下面就让小编来为大家介绍一下这篇托福听力TPO3学习笔记的内容吧,这是小编的一些见解,以便帮助大家更加充分的理解TPO真题,希望能够给正在准备托福听力的考友们带来帮助。
一、难词注解preserved adj. 保藏的;腌制的;喝醉的primitive adj. 原始的,远古的;简单的,粗糙的masterpieces n. 杰作;绝无仅有的人speculate vi. 推测;投机;思索rhinoceros n. [脊椎] 犀牛torch n. 火把,火炬;手电筒;启发之物二、长难句分析That would make them not just older than any other cave art, but about twice as old as the art in the caves at Altamira or Lascaux, which you may have heard of.这使得这些壁画不仅比其他洞窟艺术更为古远,更是尔塔米粒和拉斯科洞窟中的艺术作品年代的两倍。
你可能听过这两个洞窟的名字。
阿难词注解:Altamira or Lascaux 尔塔米粒和拉斯科难句类型:than 比较级,以及定语从句难句拆分:than 比较级的运用,twice as old as句式的运用,最后是which引导的定语从句修饰Altamira or Lascaux三、考题对应考点6.开头原则之直入主题式,(原文中)Some of the world’s oldest preserved art is the cave art of Europe, most of it in Spain andFrance. And the earliest cave paintings found to date are those of the Chauvet Cave in France discovered in 1994.Pro的第一句话就揭示了他这节课的主题是ealiestcave也就是A选项中的同义转换,所以答案选A7.举例原则,提到他女儿的例子是要引起大家的注意,(原文中)And you know, I remember when I heard about the results of the dating of the Chauvet paintings, I said to my wife, ―Can you believethese paintings are over 30,000 years old?‖ And my3-yearold daughter piped up and said, ―Is that older than my great-grandmother?‖ That was the oldest age she knew.那么从pro 描述他听到dating的消息以及家人的反映可以看出,这是为了体现这cave painting的年代久远,所以选D8.转折原则,but后面的是重点I mean, we tend to think that people who lived at that time must have been pretty primitive. But I’m gonna show you some slides in a few minutes and I think you will agree with me that this art is anything but primitive. They are masterpieces. Pro先说人们对于那时的人的映像是十分原始的,从but后转折的内容anything but primitive. They are masterpieces. 可以看出PRO给予了极高的肯定也就是It is extremely well done.所以选择A9.结果原则And people did go see the art. There are charcoal marks from their torches on the cave walls clearly dating from thousands of years after the paintings were made. So we can tell people went there.也就是说这些marks意味着人们在这些作品完成很久之后,去看了这些洞内的作品,所以答案选B10.转折原则,"But earlier at Chauvet, there is a significant interest in large dangerous animals, lots of rhinoceros, lions, mammoth, bears." 问的是作品中涉及的动物具有怎样的特别之处,在听的时候要特别注意but后面的内容,所以答案是"Many of them are dangerous",也就是B11.问答原则,D选项出自"Deep inside a cave like that is not really a place you’d want to stay, so, why? What inspired thePaleolithic artists to make such beautiful art in such inaccessible places? "C选项出自"why these preciseanimals?",根据同义转换,可知答案为CD。
TPO1-3听力题目托福TPO 1-3 Listening QuestionsTPO1 Lecture 1 5TPO1 Lecture 2 6TPO1 Conversation 2 8TPO1 Lecture 3 8TPO1 Lecture 4 9TPO2 Conversation 1 11TPO2 Lecture 1 11TPO2 Lecture 2 12TPO2 Conversation 2 13TPO2 Lecture 3 14TPO2 Lecture 4 15TPO3 Conversation 1 16TPO3 Lecture 1 17TPO3 Lecture 2 18TPO3 Conversation 2 19TPO3 Lecture 3 20TPO3 Lecture 4 21TPO4 Conversation 1 22TPO4 Lecture 1 23TPO4 Lecture 2 24TPO4 Conversation 2 25TPO4 Lecture 3 26TPO4 Lecture 4 27TPO5 Conversation 1 29TPO5 Lecture 1 29TPO5 Lecture 2 30TPO5 Conversation 2 32TPO5 Lecture 3 32TPO5 Lecture 4 33TPO6 Conversation 1 35TPO6 Lecture 1 36TPO6 Lecture 2 37TPO6 Conversation 2 38TPO6 Lecture 3 38TPO7 Conversation 1 41 TPO7 Lecture 1 41 TPO7 Lecture 2 42 TPO7 Conversation 2 43 TPO7 Lecture 3 44 TPO7 Lecture 4 45 TPO8 Conversation 1 46 TPO8 Lecture 1 47 TPO8 Lecture 2 49 TPO8 Conversation 2 50 TPO8 Lecture 3 51 TPO8 Lecture 4 52 TPO9 Conversation1 54 TPO9 Lecture 1 55 TPO9 Lecture 2 56 TPO9 Conversation 2 57 TPO9 Lecture 3 58 TPO9 Lecture 4 59 TPO10 Conversation 1 61 TPO10 Lecture 1 63 TPO10 Lecture 2 64 TPO10 Conversation 2 65 TPO10 Lecture 3 66 TPO10 Lecture 4 67 TPO11 Conversation 1 69 TPO11 Lecture 1 70 TPO11 Lecture 2 71 TPO11 Conversation 2 72 TPO11 Lecture 3 73 TPO11 Lecture 4 74 TPO12 Conversation 1 75 TPO12 Lecture 1 76 TPO12 Lecture 2 77 TPO12 Conversation 2 78 TPO12 Lecture 3 79 TPO12 Lecture 4 80 TPO13 Conversation 1 81TPO13 Lecture 2 83 TPO13 Conversation 2 85 TPO13 Lecture 3 86 TPO13 Lecture 4 87 TPO14 Conversation 1 88 TPO14 Lecture 1 89 TPO14 Lecture 2 91 TPO14 Conversation 2 92 TPO14 Lecture 3 93 TPO14 Lecture 4 94 TPO15 Conversation 1 95 TPO15 Lecture 1 96 TPO15 Lecture 2 97 TPO15 Conversation 2 99 TPO15 Lecture 3 100 TPO15 Lecture 4 101 Tpo16 Conversation 1 102 TPO16 Lecture 1 103 TPO16 Lecture 2 105 TPO16 Conversation 2 106 TPO16 Lecture 3 107 TPO16 Lecture 4 108 Tpo-17 Conversation 1 110 TPO17 Lecture 1 111 TPO17 Lecture 2 112 TPO 17 Conversation 2 113 TPO 17 Lecture 3 114 TPO17 Lecture 4 115 TPO 18 Conversation 1 117 TPO 18 Lecture 1 117 TPO 18 Lecture 2 118 TPO 18 Conversation 2 119 TPO 18 Lecture 3 119 TPO 18 Lecture 4 120 TPO 19 Conversation 1 121 TPO 19 Lecture 1 122 TPO 19 Lecture 2 123TPO 19 Conversation 2 124TPO 19 Lecture 3 125TPO 19 Lecture 4 126TPO 20 Conversation 1 127TPO 20 Lecture 1 128TPO 20 Lecture 2 129TPO 20 Conversation 2 130TPO 20 Lecture 3 131TPO 20 Lecture 4 133TPO 21 Conversation 1 134TPO 21 Lecture 1 135TPO 21 Lecture 2 136TPO 21 Conversation 2 137TPO 21 Lecture 3 138TPO 21 Lecture 4 139TPO 22 Conversation 1 140TPO 22 Lecture 1 141TPO 22 Lecture 2 142TPO 22 Conversation 2 143TPO 22 Lecture 3 144TPO 22 Lecture 4 145TPO 23 Conversation 1 146TPO 23 Lecture 1 148TPO 23 Lecture 2 149TPO 23 Conversation 2 151TPO 23 Lecture 3 152TPO 23 Lecture 4 153TPO 24 Lecture 4 156TPO1 Conversation 11. Why does the student go to see the librarian?To sign up for a seminar on using electronic sources for research To report that a journal is missing from the reference areaTo find out the procedure for checking out journal articlesTo ask about how to look for resources for a class paper2.What does the librarian say about the availability of journals and articles in the library?They are not easy to find if a professor put them on reserveMost of them are accessible in an electronic formatMost of them can be checked out for three weeksPrinted versions from the past three years are located in the reference section.3.What does the librarian suggest the student should do to save time?Choose an easier research topicConcentrate on five journalsRead the summaries of the articles firstInstall a new program on her home computer4.What can be inferred about why the woman decides to use the computer in the library? She thinks she might need additional help from the manShe does not have a computer at homeShe has to hand in her assignment by the end of the dayShe will be meeting a friend in the library later on5.Why does the woman say this()She had forgotten about the informationShe is surprised she was not aware of the informationShe is annoyed that the information was published only recentlyShe is concerned that the librarian gave her incorrect informationTPO1 Lecture 16.What is the purpose of the lecture?To explain the difference between two artistic stylesTo describe a new art gallery to the classTo introduce an artist's work to the classTo show how artists' styles can evolve over time7.What does the professor say about Frantzen's painting of a farm scene?It resembles a photographIt may be Frantzen's best known paintingIt was painted in the Impressionist styleIt was painted while Frantzen lived abroad8.Why did Frantzen go to the Sales Barn?To study human form and movementTo earn money by painting portraitsTo paint farm animals in an outdoor settingTo meet people who could model for her paining9.What does the professor imply about the painting of the young woman surrounded by pumpkins?It was painted at an art fairIt combines Impressionism with RealismIt convinced Frantzen that she was a good illustratorIt was originally meant to be used in an advertisement10.Why does the professor discuss Frantzen's difficulties as a young painter?He wants to point out mistakes that young artists commonly makeHe thinks her example can inspire the students in their own livesHer difficulties remind him of the difficulties he himself experienced as a young girl Her difficulties are the subject of some of the paintings in the gallery that the students will visit11.What does the professor imply when he says this()The students can understand Frantzen's art without knowing about her lifeThe students should pay very close attention to what he is going to saySome of his students are already familiar with Frantzen's life storySome of his students may not appreciate Frantzen's workTPO1 Lecture 212.What does the professor mainly discuss?The difference in age among American mountain rangesThe importance of a technique used for dating geological materialsThe recent discovery of an ancient canyonA comparison of various minerals used for dating13.Before the use of uranium-lead analysis, where did most geologists think the Grand Canyon sandstone came from?An ancient lake located in the American SouthwestA desert that once connected two continentsSands carried by a river from the Appalachian MountainsA nearby mountain range that had flattened out over time14.In the talk, the professor describes the sequence of uranium-lead dating. Summarize the sequence by putting the events in the correct order.Drag your answer choices to spaces where they belong. To remove an answer choice, click on itZircon in the sandstone is matched to the zircon in a particular mountain range.The amount of lead in sandstone zircon is measuredThe age of zircon in a sandstone sample is determined12315.According to the professor, what change has caused uranium-lead dating to gain popularity recently?It can be performed outside a laboratoryIt can now be done more efficientlyIt no longer involves radioactive elementsIt can be used in fields other than geology16.Why does the professor talk about the breaking apart of Earth's continents?To give another example of how uranium-lead dating might be usefulTo explain how the Grand Canyon was formedTo demonstrate how difficult uranium-lead dating isTo disprove a theory about the age of Earth's first mountain ranges17.What does the professor imply when he says this()The class is easier than other geology classesThe class has already studied the information he is discussingSome students should take a course in geological dating techniquesHe will discuss the topic later in the classTPO1 Conversation 21.What is the conversation mainly aboutA lesson Matthew prepared for his studentsA class Matthew has been observingA term paper that Matthew has writtenA problem in Matthew's classroom2.What is Matthew's opinion about observing Mr.Grabell's third-grade class? It will help him become a more effective teacherIt could help improve his study habitsIt has improved his public-speaking skillsIt may be the most difficult assignment he has had3.Why does Matthew mention Greek and Roman mythology?To identify a topic frequently discussed in third gradeTo get the professor's opinion about a lesson he taughtTo make a suggestion to improve the class he is takingTo illustrate a technique used to teach a third-grade class4.What important skills did Mr.Grabell introduce to his third-grade class?Click on 3 answersReviewing other student's reportsUsing books in the libraryInterviewing their classmatesSpeaking in publicWriting reports5.What will Matthew probably do in next Wednesday's class?Hand in his assignment earlyTry to start a study groupMake a presentation to the classChoose a topic for his paperTPO1 Lecture 36.What is the lecture mainly about?Art in the Neolithic periodThe site of a Neolithic townMethods of making stone toolsThe domestication of plants and animals by early farmers7.What does the professor imply about the tools used by the people of Catalhoyuk?They were made of stone that came from CatalhoyukThey were among the sharpest tools available at the timeThey were often used in religious ritualsThey were used primarily for agriculture8.What does the professor say about the entrances to the horses in Catalhoyuk?Click on 2 answersThey were in the roofThey were usually kept closedThey allowed smoke to escape from the houseThey stood opposite one another across narrow streets9.What does the professor say about Catalhoyuk graves?The graves contained precious stonesMany people were buried in each graveThe grave were located under the house floorsThe graves contained ashes rather than bones10.What does the professor think of the idea that the inhabitants of Catalhoyuk deliberately arranged their house so that they could live near their ancestors' graves?She thinks it is a good guess, but only a guessShe thinks some evidence supports it, but other evidence contradicts it.She thinks that further excavations will soon disprove itShe thinks that it is not appropriate to make such guesses about the distant past11.What are three things the professor says about the artwork of Catalhoyuk? Click on 3 answersIt was clearly important to the Catalhoyuk religionIt became covered with sootIt often shows farmers at workIts significance is unknownIt contains many hunting scenesTPO1 Lecture 412.What is the main topic of the lectureThe types of habitats marmots preferMethods of observing marmot behaviorFeeding habits of some marmot speciesDifferences in behavior between marmot species13.According to the case study, why are marmots ideal for observationThey do not hide from humansThey reside in many regions throughout North AmericaThey are active in open areas during the dayTheir burrows are easy to locate14.Drag the appropriate description of each marmot species' behavior to the box below the marmot's nameClick on a phrase. Then drag it to the space where it belongs.One of the phrases will not be usedDisplays aggressive tendencies is family oriented says active during the winterOlympic Marmot Eastern Marmot15.What reason does the professor give for the difference in marmot behaviour patterns?Type of food availableThe size of the populationInteraction with other marmot speciesAdaptations to the climate16.Why does the professor say this()To inform the student that his definition is incorrectTo suggest that the student did not do the readingTo encourage the student to try againTo change the topic of discussion17.Why does the professor say this()To express a similar concernTo encourage the student to explain what she meansTo address the student's concernTo agree with the studentTPO2 Conversation 11.Why does the man go to see his professorTo borrow some charts and graphs from herTo ask her to explain some statistical proceduresTo talk about report he is writingTo discuss a grade he got on a paper2.What information will the man include in his report?Click in the correct box for each phraseInclude in report Not include in reportClimate chartsInterviews with meteorologistsJournals notesStatistical tests3.Why does the professor tell the man about the appointment at the doctor's office? To demonstrate a way of remembering thingsTo explain why she needs to leave soonTo illustrate a point that appears in his reportTo emphasize the importance of good health4.What does the professor offer to do for the manHelp him collect more data in other areas of the stateSubmit his research findings for publicationGive him the doctor's telephone numberReview the first version of his report5.Why does the professor say this()To question the length of the paperTo offer encouragementTo dispute the data sourcesTo explain a theoryTPO2 Lecture 16.What is the professor mainly discussingThe development of motor skills in childrenHow psychologists measure muscle activity in the throatA theory about the relationship between muscle activity and thinkingA study on deaf people's problem-solving techniques7.Why does the professor say this()To give an example of a laryngeal habitTo explain the meaning of a termTo explain why he is discussing laryngeal habitsTo remind students of a point he had discussed previously8.Why does the professor say about people who use sign languageIt is not possible to study their thinking habitsThey exhibit laryngeal habitsThe muscles in their hands move when they solve problemsThey do not exhibit ideomotor action9.What point does the professor make when he refers to the university libraryA study on problem solving took place thereStudents should go there to read more about behaviorismStudents' eyes will turn toward it if they think about itHe learned about William James' concept of thinking there10.The professor describes a magic trick to the class,what does the magic trick demonstrate?An action people make that they are not aware ofThat behaviorists are not really scientistsHow psychologists study childrenA method for remembering locations11.What is the professor's opinion of the motor theory of thinkingMost of the evidence he has collected contradicts itIt explains adult behavior better than it explains child behaviorIt is the most valid theory of thinking at the present timeIt cannot be completely proved or disprovedTPO2 Lecture 212.What aspect of Manila hemp fibers does the professor mainly discuss in the lectureSimilarities between cotton fibers and manila hemp fibersVarious types of manila hemp fibersThe economic importance of Manila hemp fibersA use of Manila hemp fibers13.Why does the professor mention going away for the weekend?To tell the class a jokeTo apologize for not completing some workTo introduce the topic of the lectureTo encourage students to ask about her trip14.What does the professor imply about the name Manila hempIt is a commercial brand namePart of the name is inappropriateThe name has recently changedThe name was first used in the 1940's15.Why does the professor mention the Golden Gate Bridge?To demonstrate a disadvantage of steel cablesTo give an example of the creative use of colorTo show that steel cables are able to resist salt waterTo give an example of a use of Manila hemp16.According to the professor, what was the main reason that many ships used Manila hemp ropes instead of steel cables?Manila hemp was cheaperManila hemp was easier to produceManila hemp is more resistant to salt waterManila hemp is lighter in weight17.According to the lecture, what are two ways to increase the strength or rope made from Manila hemp fibers?Click on 2 answersCoat the fibers with zinc-based paintCombine the fibers into bundlesSoak bundles of fibers in salt waterTwist bundles of fibersTPO2 Conversation 21.What are the students mainly discussing?Click on 2 answersTheir courses for next semesterTheir plans for the weekendA poetry clubA class assignment2.What does the man plan to do at the end of the monthRegister for classesFinish writing his master's thesisLeave his job at the coffee shopTake a short vacation3.Why does the man talk to the woman about the "Poetry Kitchen"?To find out how often the club meetsTo inform her that the date of the next meeting has changedTo complain that not enough people are reading their poemsTo encourage her to attend4.What is the woman's attitude toward participating in the poetry club?She is looking forward to hearing her professor's poetryShe is interested in attending but she has no timeShe thinks the poetry that is read there is not very goodShe used to participate but did not enjoy it5.What will the students do in the summerThey will both take coursesThey will both have full-time jobsThey will travel to England togetherThey will teach a class togetherTPO2 Lecture 36.What is the main purpose of the lecture?To illustrate the importance of extrinsic valuesTo explain Aristotle's views about the importance of teachingTo explain why people change what they valueTo discuss Aristotle's views about human happiness7.The professor gives examples of things that have value for her. Indicate for each example what type of value it has for her.Click in the correct box. This question is worth 2 points.Only extrinsic value Only intrinsic value Both extrinsic and intrinsic value TeachingExercisehealthPlaying a musical instrument8.Why is happiness central to Aristotle's theory?Because it is so difficult for people to attainBecause it is valued for its own sake by all peopleBecause it is a means to a productive lifeBecause most people agree about what happiness is9.According to the professor, why does Aristotle think that fame cannot provide true happiness?Fame cannot be obtained without help from other peopleFame cannot be obtained by all peopleFame does not last foreverPeople cannot share their fame with other people10.What does the professor mean when she says this()Teaching is not a highly valued profession in societyShe may change professions in order to earn more moneyThe reason she is a teacher has little to do with her salaryMore people would become teachers if the salary were higher11.What is Bode's law?A law of gravitationAn estimate of the distance between Mars and JupiterA prediction of how many asteroids there areA pattern in the spacing of the planetsTPO2 Lecture 412.Why does the professor explain Bode's Law to the class?To describe the size of the asteroidsTo explain who the asteroids belt was discoveredTo explain how gravitational forces influence the planetsTo describe the impact of telescopes on astronomy13.How does the professor introduce Bode's Law?By demonstrating how it is derived mathematicallyBy describing the discovery of UranusBy drawing attention to the inaccuracy of a certain patternBy telling the names of several of the asteroids14.According to the professor, what two factors contributed to the discovery of the asteroid Ceres?Click on 2 answersImproved telescopesAdvances in mathematicsThe discovery of a new starThe position of Uranus in a pattern15.What does the professor imply about the asteroid belt?It is farther from the Sun than UranusBode believed it was made up of small starsIt is located where people expected to find a planetCeres is the only one of the asteroids that can be seen without a telescope16.Why does the professor say thisTo introduce an alternative application of Bode's LawTo give an example of what Bode's law cannot explainTo describe the limitaions of gravitational theoryTo contrast Bode's Law with a real scientific lawTPO3 Conversation 1Q1Why does the women come to the office?To notify the university of her change of addressTo find out where her physics class is being heldTo get directions to the science buildingTo complain about her physics class being canceledQ2What happened to the letter the university sent to the woman?She threw it away by mistakeHer roommate forgot to give it to herIt was sent to her old mailing addressIt was sent to another student by mistakeQ3Why was the woman’s physics class canceled?Not enough students signed up to take the classNo professors were available to teach the classThe university changed its requirements for physics studentsThere were no classrooms available in the science building at the hourQ4What does the man suggest the woman do before the beginning of next semester? Consult with her advisor about her class scheduleCheck with the registrar’s office about the location of the classRegister for her classes earlyCall the physics departmentQ5RWhat does the man imply when he say this:He know the physics class has been canceledHe is not sure where the science building isMany of the room assignments have been changedThe women can check for herself where her class isTPO3 Lecture 1Q6What does the professor mainly discuss?Major changes in the migratory patterns of hummingbirdsThe adaptation of hummingbirds to urban environmentsConcern about the reduction of hummingbird habitatThe impact of ecotourism on hummingbird populationsQ7What does the professor imply might cause a decrease in the hummingbird population?An increase in the ecotourism industryAn increase in the use of land to raise crops and cattleA decrease in banding studiesA decrease in the distance traveled during migrationQ8What does the professor say people have done to help hummingbirds survive?They have built a series of hummingbird feeding stationsThey have supported new laws that punish polluters of wildlife habitatsThey have replanted native flowers in once polluted areasThey have learned to identify various hummingbird speciesQ9What way of collecting information about migrating hummingbirds does the professor mention?Receiving radio signals from electronic tracking devicesBeing contacted by people who recapture banded birdsCounting the birds that return to the same region every yearComparing old and young birds’ migration routesQ10What does the professor imply researchers have learned while studying hummingbird migration?Hummingbirds have totally disappeared from some countries due to recent habitat destructionPrograms to replant flowers native to hummingbird habitats are not succeeding Some groups of hummingbirds have changed their migration patternsSome plant species pollinated by hummingbirds have become extinctQ11RWhat does the professor imply when she say this:There is disagreement about the idea she has presentedShe does not plan to discuss all the detailsHer next point may seem to contradict what she has just saidThe point she will make next should be obvious to the studentsTPO3 Lecture 2Q12What is the main purpose of the lecture?To discuss the style of an early filmmakerTo describe different types of filmmaking in the 1930sTo discuss the emergence of the documentary filmTo describe Painleve’s influence on today’s science-fiction filmsQ13Why are Painleve’s films typical of the films of the 1920s and 1930s?They do not have soundThey are filmed underwaterThey are easy to understandThey difficult to categorizeQ14According to the professor, how did Painleve’s film confuse the audience?They show animals out of their natural habitatThey depict animals as having both human and animal characteristicsThe narration is scientific and difficult to understandThe audiences of the 1920s and 1930s were not used to films shot underwaterQ15Why does the professor mention sea horses?To explain that they were difficult to film in the 1930sTo point out that Cousteau made documentaries about themTo illustrate Pianleve’s fascination with unusual animalsTo explain why Painleve’s underwater films were not successfulQ16Why does the professor compare the film style of Jacques Cousteau and Jean Painleve?To explain how Painleve influenced CousteauTo emphasize the uniqueness of Painleve’s filming styleTo emphasize the artistic value of Cousteau’s documentary filmsT o demonstrate the superiority of Painleve’s filmmaking equipmentQ17RWhat does the student imply when he say this:He does not like Jean Painleve’s filmsHe thinks that the professor should spend more time discussing Jacques Cousteau’s filmHe believes that high quality filmmakers are usually well knownHe believes that Jean Painleve’s film have been unfairly overlookedTPO3 Conversation 2Q1Why does the student go to see the professor?To ask about a class assignmentTo find out about a midsemester projectTo get information about summer jobsTo discuss ways to improve his gradeQ2What was originally located on the site of the lecture hall?A farmhouseA pottery factoryA clothing storeA bottle-manufacturing plantQ3What is mentioned as an advantage of working on this project?Off-campus travel is paid offStudents can leave class earlyThe location is convenientIt fulfills a graduation requirementQ4What is the professor considering doing to get move volunteers?Offering extra class creditPaying the students for their timeAsking for student volunteers from outside her classProviding flexible work schedulesQ5What information does the student still need to get from the professor? The name of the senior researcherWhat book he needs to read before the next lectureWhen the train session will be scheduledWhere the project is locatedTPO3 Lecture 3Q6What does the professor mainly discuss?The oldest known cave artHow ancient cave art is datedThe homes of Paleolithic humansHow Paleolithic humans thought about animalsQ7When does the professor mention his daughter?To describe her reaction to seeing the paintingsTo explain the universal appeal for the Chauvet paintingsTo demonstrate the size of most Paleolithic cave artTo emphasize his point about the age of Chauvet paintingsQ8What is the professor’s opinion about the art at the Chauvet cave?It is extremely well doneIt probably reflected artists’ religious beliefsIt is less sophisticated than the art at Lascaux and AltamiraIt is probably not much older than the are at Lascaux and AltamiraQ9According to the professor, what is the significance of charcoal marks on the walls of the Chauvet cave?They suggest that Paleolithic people cooked their food in the caveThey prove that people came to the cave long after the paintings were madeThey show how much light the Paleolithic artists needed for their workThey were used in recent times to date the paintingsQ10Compared to other Paleolithic art, what is unusual about the animals painted at Chauvet?Most of them are horsesMany of them are dangerousMany of them are shown alongside humansAll of them are species that are still found in FranceQ11What are two questions about the Chauvet cave artists that the professor raises but cannot answer?Choice two answers belowHow they lighted their work areaHow they obtained pigments for their paintsWhy they chose to paint certain animals and not othersWhy they placed their art in dark, uninhabited placesTPO3 Lecture 4Q12What is the lecture mainly about?Different ways of magnifying the spectrum of a starHow a chemical element was first discovered on the SunHow astronomers identify the chemical elements in a starWhy the spectra of different stars are composed of different colors。
官方真题Official35托福听力Lecture4对话原文免费分享(原TPO)官方真题Official模考软件一直是考生不可或缺的一个备考工具,很多托福考生都在用这个。
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官方真题Official35托福听力Lecture 4对话原文免费分享(原TPO)官方真题Official 35-L4Narrator:Listen to part of a lecture in an Earth science class.Professor:Let's review something from last week. We talked about an event that happened 65 million years ago. Anyone?Student:An asteroid hit Earth. Um...well, we think an asteroid hit Earth, near the Yucatan Peninsula, in Mexico, and that wiped out all the dinosaurs.Professor:Right. I wouldn't say that we've got 100% proof, but there's very strong evidence that this is why that mass extinction occurred.Okay. But did you know there was an earlier extinction far greater than the one that killed off the dinosaurs? It was what we call the Permian Extinction.Now, way back about 290 million years ago, at the beginning of the Permian Period, there was just one big continent, a super continent. And as the climate warmed up, plant and animal species began to diversify profusely. So life during the PermianPeriod was abundant and diverse. But about 250 million years ago, the Permian Period ended with a rapid mass extinction, something happened that wiped out 75% of the land animals and over 95% of ocean life.So what was it? What could have caused this?Well, with the all the evidence that it was an asteroid that led to the dinosaur extinction, we began asking ourselves: is it possible that another asteroid much earlier caused the Permian Extinction? And so researchers have been looking for an impact crater.Well, with the all the evidence that it was an asteroid that led to the dinosaur extinction, we began asking ourselves: is it possible that another asteroid much earlier caused the Permian Extinction? And so researchers have been looking for an impact crater.Student:I thought the Permian Extinction was caused by a decline in sea water oxygen levels. Isn't that what's in the textbook?Professor:But don't forget the textbook makes it very clear that's only a theory.Student:And it mentions something about volcanic eruptions too.Professor:It does, but now this new theory has led to a search for evidence of an asteroid impact. And one place of interest is a region called Wilkes Land in eastern Antarctica.A few years ago, a researcher reported a strange anomaly beneath the ice in Wilkes Land. Evidence of what may be a mascon. That's just short for mass concentration.When an asteroid hits Earth, when it slams into Earth's crust, we think that causes molten rock from deep below the surface to rise up into the impact area. Sort of like if you bump your head, you get a big lump under the skin. Fluid makes the area swell. Anyway, the material flowing up from below the crust is more dense than the crust itself. So that's how we get a mascon, a spot in the crust with newer crust material that's more dense than the material all around it.There're lots of mascons on the moon too, where a mascon’s density causes a small increase in the local gravity that can be measured and mapped by orbiting spacecraft. And where do these mascons tend to be found? In the centers of impact craters on the moon's surface.But back to Wilkes Land. We’re not certain that the mascon there...what might be a mascon ...was actually caused by the impact of an asteroid, but there does seem to be evidence. Researchers notice a gravity anomaly similar to those on the moon. And the spot where the gravity readings are especially high...this is right in the middle of a 500-kilometer wide, circular ridge, what could be part of an old impact crater.And if there was an asteroid impact there in Wilkes Land, the next question is: did it happen 250 million years ago? Because that would put it when in geologic history?Student:At the end of the Permian Period? Right when those animals went extinct.Professor: Exactly.Student:But can't researchers figure that out by studying the rocks there in Wilkes Land...where this impact supposedly took place?Professor:Well, to get to anything from that long ago, we would have to drill down to about a mile, about 1.6 kilometers of solid ice that covers the area today. And that's not likely to happen.But speaking of rocks, I should mention that Wilkes Land is not the only place of interest here. There's another called the Bedout High off the coast of Australia. And we have rock samples from the Bedout High. Some apparently have extraterrestrial origin. I mean, they show the effects of extreme temperatures and pressures, the level of extremes produced only by an impact. And as for their age, well, they do in fact, date back to about 250 million years ago.怎样用单词推断托福听力对话场景方法可行的原因仍在于ETS的出题原则,大家肯定已经非常熟悉托福听力考试中的"学生生活原则",它是ETS坚定不移的出题原则,这一原则使托福听力从内容上永远离不了学生生活这一中心。
【托福听力备考】TPO3听力文本——Lecture 4
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Lecture 4 Astronomy
Narrator:Listen to part of a lecture in an astronomy class.
Professor:Now astronomy didn’t really bloom into the science it is today
until the development of spectroscopy.
Spectroscopy is basically the study of spectra and spectral lines of light,
and specifically for us, the light from stars. It makes it possible to analyze
the light emitted from stars. When you analyze this light, you can figure out
their distance from the Earth, and identify what they are made of, determine
their chemical composition.
Before we get into that though, it’s probably a good thing to back up a bit.
You all know how when you take a crystal prism and pass a beam of sunlight
through it, you get a spectrum, which looks like a continuous band of rainbow
colors. The light that we see with our human eyes as a band of rainbow color
falls in the range of what’s called visible light. And visible light
spectroscopy is probably the most important kind of spectroscopy.
Anyone want to take a stab at the scientific term for visible light? And I’m
sure all of you know this because you all did the reading for today.
Student:Optical radiation. But I thought being exposed to radiation is
dangerous.
Professor:Yes, and no. If you are talking about radiation, like in the element Uranium, yeah, that’s dangerous. But radiation as a general term actually refers to anything that spreads away from its source. So optical radiation is just visible light energy spreading out.
OK, so we’ve got a spectrum of a beam of sunlight and it looks like the colors bleed into each other. There are no interruptions, just a band flowing from violet to green, to yellow, to… you get the idea.
Well, what happens if the sunlight’s spectrum is magnified? Maybe you all didn’t do the reading. Well, here’s what you’d see. I want you to notice that this spectrum is interrupted by dark lines called spectral lines. If you really magnify the spectrum of the sunlight, you could identify more than 100,000 of them. They may look like kind of randomly placed, but they actually form many distinct patterns. And if you were looking at the spectrum of some other star, the colors would be the same. But the spectral lines would break it up at different places, making different patterns. Each pattern stands for a distinct chemical element, and so different sets or patterns of spectral lines mean that the star has a different chemical composition.
Student:So how do we know which spectral patterns match up with which elements?
Professor:Well, a kind of spectroscopic library of elements was compiled using flame tests. A known element, say a piece of iron for example, is heated
in a pure gas flame. The iron eventually heats to the point that it radiates
light. This light is passed through a prism, which breaks it up into a spectrum.
And a unique pattern, kind of like a chemical fingerprint of spectral lines for that element appears. This process was repeated over and over again for many different elements, so we can figure out the chemical makeup of another star by comparing the spectral pattern it has to the pattern of the elements in the library.
Oh, an interesting story about how one of the elements was discovered through spectroscopy. There was a pretty extensive library of spectral line patterns of
elements even by the 1860s. A British astronomer was analyzing a spectrograph of
sunlight, and he noticed a particular pattern of spectral lines that didn’t match anything in the library. So he put two and two together, and decided there was an element in the sun that hadn’t been discovered here on the earth yet.
Any guesses about what that element is? It actually turned out to be pretty common and I’m sure all of you know it.
OK. Let’s try something else. Any of you happened to be familiar with the Greek word for “sun” by chance?
Student: Something like “Helius” or something like that. Oh, it must be “Helium”. So you are saying that Helium was discovered on the sun first.
Professor:Yes, and this is a good example of how important spectroscopy is in astronomy.。