it/one/that的用法和区别
I. it／one ／that三者均可用作代词, 指代前面提到的名词。一般说来, it指代同名同物; one与that则指代同名异物。
II. one与that虽可用来指代同名异物, 但one为泛指, 相当于a／an＋名
词; that为特指, 相当于the ＋名词。所以one所指代的名词的修饰语一般为 a ／an ／some ／any; that所指代的名词的修饰语往往是the ／this ／that。
III. one只能代替可数名词单数, 代替可数名词复数时用ones; that既可以代替不可数名词也可以代替可数名词单数, 代替可数名词复数时用 those。
IV. one既可代替事物, 也可代替人, that只能代替事物而不能代替人。有时可以用the one或the ones代替that或those。
V. one一般有前置修饰语, 有时也可有后置修饰语或不用修饰语。而 that 不能
高中英语语法：It的完整用法精讲 it可用作人称代词、指示代词、先行词及引导词等。 1. 人称代词it，是第三人称单数中性，代表前文已提到过的一件事物。如： 1）That vase is valuable. It's more than 200 years old. 那个花瓶很珍贵，它有200多年的历史。 2）I love swimming. It keeps me fit. 我喜欢游泳，它能使我保持健康。 当说话者不清楚或无必要知道说话对象的性别时，也可用it来表示。如： 3）It's a lovely baby. Is it a boy or a girl? 宝宝真可爱，是男孩还是女孩？ it可用来指代团体。如： 4）The committee has met and it has rejected the proposal. 委员会已开过会，拒绝了这项建议。 it用以代替指示代词this, that.如： 5）--- What's this? --- It's a pen. —这是什么？—是一支钢笔。 6）--- Whose book is that? --- It's Mike's. —那是谁的书？—是迈克的。 2. 指示代词it，常用以指人。如： 7）Go and see who it is. 去看看是谁。 8）--- Who is making such a noise? —是谁发出这样的吵闹声？ --- It must be the children. —一定是孩子们。 3.虚义it无指代性，常用作没有具体意义的主语，出现于表示天气、气候、温度、时间、地点、距离等意义的句子中。如： 9）It is half past three now. 现在是三点半钟。 10）It is six miles to the nearest hospital from here. 这里离最近的医院也有六英里。 11）It was very cold; it snowed and grew dark. 天气很冷；天下着雪，渐渐地变黑了。 it也常用来表示一般的笼统的情况。如： 12）It's awful—I've got so much work I don't know where to start. 糟透了——我有这么多工作要做我不知从何开始。 13）How is it going with you? 你近况如何？ 14）Take it easy. 不要紧张。 it也常用于下列结构： 15）It looks as if the college is very small. 看起来这个学院很小。 16）It seems as though our plan will be perfect. 似乎我们的计划很完善。 17）It's my turn. 该轮到我了。 it也常用于某些习惯用语中作宾语，各该习惯用语有具体意义，但it并无具体意义。如：cab it 乘车catch it 受责，受罚come it 尽自己分内come it strong 做得过分walk it 步行make it 办成take it out of somebody 拿某人出气 4. 先行词it. it充当形式主语或形式宾语，本身无意义，只起一种先行引导的作用，先行词不重读。后面的真正主语或真正宾语通常是不定式结构、-ing分词结构或名词性从句。 （1）用作形式主语
英语中使用that 1.先行词如果有all, every, only, very, any (任何的)，one of few,any,little, no等词修饰时， 2.先行词是不定代词，some（something，somebody，someone），any（anything，anybody，anyone），no（nothing，nobody，no one），every（everything，everybody，everyone 3.先行词有最高级修饰 4.先行词有序数词修饰， 5.先行词如果既有人又有事物 6. 主句以There be…开头,先行词为物时用that,先行词为人的句子中,常用who引导定语从句. . There is a room in the building that is still free. There is a pretty girl who wants to see you. 7. 句子中如果已经有了who，引导词代替人，为了避免重复，要使用that；或者句子中如果已经有了which，引导词代替事物，为了避免重复，要使用that； 8. 先行词如果在主句中做表语，或引导词在从句中做表语，代替事物，多使用that；eg. 这是我昨天买的书。This is the book that I bought yesterday. as作为定语从句引导词的三点用法 （1）代替主句整句话内容； （2）先行词有such修饰，要使用as； eg. He is such a good teacher __as__ we all like. He is such a good teacher __that___ we all like him. (such…that 如此…以至于…,引导结果状语从句)； （3）先行词有the same修饰， the same……as表示同类不同一个：I want to buy the same bicycle as my friend did. the same……that表示同类同一个：The police has found the same bicycle that Jack lost. 引导词代替主句整句话内容，在从句中做主语或宾语，要使用as或which来引导 ?as和which的区别： 1.结构上as的从句既可以放于主句前，也可以放于主句后；which的从句只能放于 主句后； 2.as如果在从句中做主语，谓语动词只能是be动词结构； eg. 她数学考试不及格，这让她的爸爸很生气。
it的用法及练习 一、概述 在英语中，it的使用相当广泛，它既可用作代词，如人称代词（personal it）、指示代词（demonstrative it）及非人称代词（impersonal it）, 也可用作引导词（anticipatory it）和强调结构中的强调词（emphatic it） Someone is ringing the doorbell. Go and see who it is.有人在按门铃。去看看是谁。（人称代词）What’s this?这是什么？ It’s a book.这是一本书。（指示代词） What a long way it is from Beijing to London! 从北京到伦敦真远。（非人称代词） It's best to plant trees in spring because it's warmer.春天是植树的最佳时节，因为天气更暖和。（作引导词） It was I who met him in the park last week. 是我上星期在公园遇到他的。（强调结构中的强调词） 二、it作代词 1、用作人称代词（personal it） 代替前文提到过的事物，it作真实主语或宾语。 The frog is not a warm-blooded animal. It is a cold-blooded one.青蛙不是温血动物，它是冷血动物。My pen is missing. I can't find it anywhere. 我的笔丢了，我哪儿也找不到它了。 I won't be back tonight. Please tell my wife about it .我今晚不回来了，请你向我妻子说一声。 I was disappointed with the film. I had expected it to be much better. 我对这部电影很失望，我曾盼望它更好。 Tom's mother kept telling him that he should work harder, but it didn't help.汤姆的妈妈不停地告诉他要努力，但这没起作用。 2、用作指示代词（demonstrative it） 相当于this或that，it有时不特指某件东西，而代表前面已提到的或将会发生的某件事情。 -Who is knocking at the door? —谁在敲门？
so...that... 如此……以致于…… ...so that... 以便于，为了 “so...that...”句型的意思是“如此/这么……以致于……”，常引导结果状语从句，但“so...that...”是个爱“变脸”句型，你一不留意就会出错。“so...that...”句型及其转换也是中考的热点，现将其用法总结归纳如下，让我们一起来看看它是怎样变的吧。 一、 so... that...句型中的so是副词，常常用来修饰形容词或副词，常用句型为：主语+谓语+so+adj. / adv. + that从句。例如： 1. he is so young that she can't look after herself. 2. The boy ran so fast that I couldn't catch him. 3. He was so angry that he couldn't say a word. / 二、在“such... that...”句型中，such修饰名词，意思也是“如此……以致于……”但当名词前有many、much、(a) few、(a) little等词修饰时，句子中要用“so...that...”而不能用“such...that...”。例如： 1. He has so much money that he can buy what he wanted. 2. I've had so many falls that I have pains here and there. 3. There is little water in the glass that I can't drink any more. 三、 so与that也可连起来写，即变成：... so that ...(以便 / 为了……)，引导目的状语从句。例如： ~ 1. I got up early so that I could catch the early bus. 2. Please open the window so that we can breathe fresh air. 3. You must go now so that you won't be late. 四、以“so...that”引导的结果状语从句可以转换成不定式的简单句，即可转换为“...enough to...”或“...too...to”句型，但这种转换必须符合下列条件： 1. 当主句和从句的主语一致，且that从句是肯定句时，可用“enough to do sth.”来转换。例如：
Section_—it的用法(1) 语法图解 探究发现 ①It is a beautiful day here and I am sitting under the big tree at the end of the garden. ②Your mother tells me that you started smoking some time ago and now you are finding it difficult to give it up. ③It is never too late to mend. ④It is no use talking to them. ⑤It is said that he stole the money. ⑥I think it difficult to learn English well. ⑦We make it clear that speaking to the teacher in that way is not polite. ⑧I don't like it when people talk with the mouth full of food. [我的发现] (1)①句it表示天气，②句第一个it代替to_give_it_up作形式宾语；第二个it代替句中所说的“吸烟”的事。 (2)在句③④⑤中it用作形式主语，其中句③用在“It is＋形容词＋(for/of＋sb.)＋动词不定式(短语)”中，it指代动词不定式(短语)；句④用在“It is＋no use/good＋动名词(短语)”中，it指代动名词(短语)；句⑤用在“It is＋said/believed/reported＋that从句”中，it指代that 从句。 (3)在句⑥⑦⑧中it用作形式宾语，其中句⑥用在“动词＋it＋形容词＋动词不定式(短语)”中，it指代动词不定式(短语)，句⑦用在“动词＋it＋形容词＋that从句”中，指代that 从句；句⑧it用在某些特殊的句式中，指代when从句。 一、it用作人称代词和非人称代词 1．用作人称代词 (1)it用来指代前面的名词或前面提到过的事。 My friend offered me a beautiful gift yesterday, and I like it very much. 我朋友昨天给了我一件漂亮的礼物，我非常喜欢。
It作形式主语常见句型 动词不定式，动名词或主语从句作主语时，通常把它们放在谓语动词前，而用it作形式主语，放到句首，常见句型有： 1. It + be + 形容词+主语从句，如： It is uncertain whether he can come to Jenny’s birthday party or not. 2. It + be + 名词词组+ 主语从句，这类名词有：a fact, a pity, a shame, an honour， a question等，如： It’s a pity that you missed the exciting football match. It remains a question whether he will come or not. 3. It + be + 过去分词+ 主语从句，这类过去分词有：announced, believed, expected, hoped, decided, reported, said, shown等，如： It is reported that 16 people were killed in the earthquake. It is not decided who will give the operation to the patient. 4. It + 不及物动词(seem, appear, happen等) + 主语从句, 这类不及物动词有：appear, happen, seem等，如： It seemed that he didn’t tell the truth. It happened that I was out when he called. 5. It + be + 形容词+ for sb.）+ 动词不定式 这类句型常用形容词easy, difficult, hard, important, possible，wise等作表语，有时候为了强调不定式动作的执行者，常在不定式前加for sb，如： It’s necessary for the young to master two foreign language. It is unwise to give the children whatever they want. 这类形容词有：easy, difficult, hard, important, possible，wise 6. It + be + 形容词+ of sb. + 动词不定式，这类形容词常是表示心理品质,性格特征的形容词，如：kind, nice stupid, clever, foolish, polite, impolite, silly, selfish, considerate 等。某人和这些形容词可以构成主系表结构。如： It’s very kind of you to help me with the work. =You are kind to help me. It seemed selfish of him not to share his dictionary with others. =He seemed selfish not to share his dictionary with others. 7. It + be +名词词组+ 动词不定式，如： It is not a good habit to stay up too late. 8. It + be + 名词或形容词+ 动名词，这类名词和形容词常常是：good, no good, no use, a waste of, useless, senseless等，如： It’s a waste of time talking to her any more. It is no use arguing about the matter with him. 9. It + take ( sb. )+ 时间（金钱）+ 动词不定式，如： It took the workers almost three years to finish building the dam. It will take a whole day to get to the top of the mountain on foot.
THAT用法总结 第一、that 用作形容词（后接复数名词时用those） 它用来指已被提到的人或物；也可表对比，指两个中较远的那个。 What about that book you borrowed from me last month？ 请注意，that 有时候在句子中具有喜欢或轻蔑等感情色彩。 that little son of his 他那个小宝贝儿子 That George！乔治那家伙！（含有轻蔑语气） 第二、that 用作代词。 1. that 用作指示代词（复数形式是those），其指代意义同形容词用法，同时它还可以用作定语从句中的先行词；还可为了避免重复，代替前述名词。 .that用来替代前面提到的特指的事物,所代替的名词可以是可数名词,也可以是不可数名词.代替可数名词可以用the one替换.但其前面不可用任何限定词修饰.例如: 1)The population of China is larger than that of Japan.(that代替不可数名词population,不可用the one替换) 2)The headteacher in your class is younger and more active than that in theirs.(that代替可数名词headteacher,可用the one替换) that 代替指物的单数可数名词或抽象不可数名词，一般是特指的 those 代替指人或指物的复数名词，一般是特指的=the ones one 代替指人或指物的单数可数名词，一般是泛指的 ones 代替指人或指物的复数名词，一般是泛指的 That is what he told me. What is that (which) you have got in your hand? The price of rice is higher than that of flour. 2. that 用作关系代词，引导限制性定语从句。先行词可人可物，用法相当于who或which。（但是在下列情况下多用that：先行词既有人又有物时；先行词有形容词最高级、序数词、不定代词、very，only等修饰时；先行词是不定代词时）He talked about the teachers and schools that he had visited. I think it one of the most wonderful films that the film company has ever produced. She has little information that is useful for our research. Is there anything that I can do for you? 请注意，that 在定语从句中作宾语时通常可省略。 The books (that) I sent you will help you in your studies. 第三、that 用作连词，引导名词性从句,状语从句和强调句。 1. that名词性从句。 ①引导宾语从句。及物动词后的引导词that可省略。 I didn't expect (that) he could win the championship. The teacher pointed out that Tom was not working hard enough.
巩固练习 Ⅰ. 把下面句子译成英语，注意it的用法。 1. 过了很久他才回来。 ________________________________________________________________________ 2. 我们两个月后才会再见面。 ________________________________________________________________________ 3. 我离开这所学校已经20年了 ________________________________________________________________________ 4. 直到她摘下墨镜我才认出她是个著名影星。 ________________________________________________________________________ 5. 是约600年前第一块带有表盘(face)和一个时针（hour hand）的钟表被制造出来的。________________________________________________________________________ 6. 昨天是他们打扫的教室。 ________________________________________________________________________ 7. 我是在大街上遇见她的父亲的。 ________________________________________________________________________ 8. 我们弄清楚了我们要在何时何地开会。 ________________________________________________________________________ 9. 据说所有的票都卖完了。 ________________________________________________________________________ 10. 我们真的该采取行动了。 ________________________________________________________________________ Ⅱ. 从方框中选出能够填入空白处的合适的连接词。 since, before, after, that, where, which 1. The weather turned out to be very good, _______ was more than we could expect. 2. It was not until ten o'clock ______ we got home last night． 3. Look at the building. It was the theatre _______ Lincoln was murdered. 4. Could it be in the restaurant in______ you had dinner with me yesterday_______ you left behind your keys and wallet? 5. It's years ______I painted this beautiful picture. 6. It will be years ______ I paint this beautiful picture. 7. It was years ______ I painted this beautiful picture. 8. It's for years ______ I have painted this beautiful picture. 9. It worried the mother a lot _______ her son drove so fast. 10. I think it important ______ you should attend the conference. Ⅲ. 单项选择。 1. I have always been honest and straightforward, and it doesn't matter ____ I am talking to. A．who is it B．who it is C．it is who D．it is whom 2. It was the ability to do the job _______ matters not where you e from or what you are.
英语中it的用法及练习 一、概述 在英语中，it的使用相当广泛，它既可用作代词，如人称代词（personal it）、指示代词（demonstrative it）及非人称代词（impersonal it）, 也可用作引导词（anticipatory it）和强调结构中的强调词（emphatic it） Someone is ringing the doorbell. Go and see who it is.有人在按门铃。去看看是谁。（人称代词）What’s this?这是什么？ It’s a book.这是一本书。（指示代词） What a long way it is from Beijing to London! 从北京到伦敦真远。（非人称代词） It's best to plant trees in spring because it's warmer.春天是植树的最佳时节，因为天气更暖和。（作引导词） It was I who met him in the park last week. 是我上星期在公园遇到他的。（强调结构中的强调词） 二、it作代词 1、用作人称代词（personal it） 代替前文提到过的事物，it作真实主语或宾语。 The frog is not a warm-blooded animal. It is a cold-blooded one.青蛙不是温血动物，它是冷血动物。 My pen is missing. I can't find it anywhere. 我的笔丢了，我哪儿也找不到它了。 I won't be back tonight. Please tell my wife about it .我今晚不回来了，请你向我妻子说一声。 I was disappointed with the film. I had expected it to be much better. 我对这部电影很失望，我曾盼望它更好。 Tom's mother kept telling him that he should work harder, but it didn't help.汤姆的妈妈不停地告诉他要努力，但这没起作用。 2、用作指示代词（demonstrative it） 相当于this或that，it有时不特指某件东西，而代表前面已提到的或将会发生的某件事情。 -Who is knocking at the door? —谁在敲门？ -It's me. —是我。 I had a talk with the student. It was very helpful to her. 我和那个学生谈了次话，对她非常有帮助。 It happened during my stay in the United States. 事情发生在我在美国的时候。 -Whose exercise book is that? —谁的作业本？ -It's his . —是他的。 3、用作非人称代词（impersonal it） 代词it可用来指除人以外的一切生物和事物，无阴阳性之分。可指时间、距离、度量、价值、自然现象（天气、气体、阴暗等）。 -What's the time? —“几点了？” -It's half past ten. —“十点半”（指时间） It is late autumn now. 现在是深秋。（指时间） It is rather cold today, isn't it?今天很冷，是不是？（指天气） -How far is it from here to the station? —从这儿到车站有多远？ -It's about two kilometers. -大约两公里。（指距离） It is raining hard. 雨下得很大。（指自然现象） -What's the cost of the dictionary? 那本词典多少钱？
“that”在英文中是一个使用频率很高的单词。它有四种词性，并且句法及语法功能纷繁复杂。同学们如果不能熟练掌握其用法，很可能会形成英语学习的一种障碍，从而影响其学习兴趣和效率。现将that的用法总结归纳如下： 第一、that 用作形容词（后接复数名词时用those）。 它用来指已被提到的人或物；也可表对比，指两个中较远的那个。 What about that book you borrowed from me last month？ 请注意，that 有时候在句子中具有喜欢或轻蔑等感情色彩。 that little son of his 他那个小宝贝儿子 That George！乔治那家伙！（含有轻蔑语气） 第二、that 用作代词。 1. that 用作指示代词（复数形式是those），其指代意义同形容词用法，同时它还可以用作定语从句中的先行词；还可为了避免重复，代替前述名词。That is what he told me. What is that (which) you have got in your hand? The price of rice is higher than that of flour. 2. that 用作关系代词，引导限制性定语从句。先行词可人可物，用法相当于who或which。（但是在下列情况下多用that：先行词既有人又有物时；先行词有形容词最高级、序数词、不定代词、very，only等修饰时；先行词是不定代词时） He talked about the teachers and schools that he had visited. I think it one of the most wonderful films that the film company has ever produced. She has little information that is useful for our research. Is there anything that I can do for you? 请注意，that 在定语从句中作宾语时通常可省略。The books (that) I sent you will help you in your studies. 第三、that 用作连词，引导名词性从句,状语从句和强调句。 1. that名词性从句。 ①引导宾语从句。及物动词后的引导词that可省略。I didn't expect (that) he could win the championship. The teacher pointed out that Tom was not working hard enough. ②引导主语从句。通常采用it作形式主语的句型。 That the earth goes around the sun is known to everyone. （It is known to everyone that the earth goes around the sun.） ③引导表语从句。 The trouble is that we are short of money. ④引导同位语从句。 引导同位语从句的that和引导定语从句的that是不同的。前者只起语法作用，在从句中不作任何成分；而后者在定语从句中作主语、宾语或表语。举例说明： The news that he resigned from office surprised us. The idea that he holds is very common nowadays on campus. 2. that引导状语从句①引导目的状语从句。 Bring it nearer that I may see it better. ②引导结果状语从句。What have I done that he should be so angry with me? ③引导原因状语从句。 I am afraid that I will fail in the driving test. ④引导让步状语从句。意为“虽然、尽管”。
it的用法 一、考点聚焦 1、it的基本用法 （1）用作人称代词，代替前文提到过的事物。 The train has arrived. It arrived half an hour ago. （2）用以代替提示代词this, that。[来源:学,科,网Z,X,X,K] —What’s this? —It’s a knife. —Whose watch is t hat? —It’s mine. （3）起指示代词的作用，指一个人或事物。 —Who is knocking at the door? —It’s me. （4）指环境情况等。 It was very noisy(quiet) at the very moment. （5）指时间、季节等。 —What time is it? —It’s eight o’clock. It often rains in summer here. （6）指距离。 It is a long way to the school. （7）作形式主语。 It is not easy to finish the work in two days. It is no use crying over spilt milk. It is as pity that you didn’t read the book. （8）作形式宾语。 I think it no use arguing w ith him. I found it very interesting to study English. He made it clear that he was not interested in that subject. （9）用于强调结构。 It was Xiaoming whom(that)I met in the street last night. It was in the street that I met Xiaoming last n ight. It ws last night that I met Xiaoming in the street. It was I who met Xiaoming in the street last night. 2、含有“It is …”的句型 （1）It is time (for sb.) to do sth. It is (high) time that sb. did sth.(虚拟语气) （2）It is + 形容词（+of / for sb.）+ to do sth 通常用 of的词有brave、clever、careful、hopeless、kind、good、naughty、nice、silly、stupid、foolish、wise 等。 （3）It is + 形容词+ that + sb. + (should) do sth.（虚拟语气）[来源:学科网ZXXK] 能用于这个句型的形容词有strange、wonderful、natural、good、proper、right、wrong、well、fortunate、important、necessary、useless、likely、probab le、impossible等。有时可省去should而直接用动词原形。如：It is important that we should pay close attention to grain. It is natural that he（should）say so. （4）It is no use/ good + doing sth. It is no use trying again = It is of no use to try again. （5）It is + 被强调部分+ that/who + …[来源:学科网ZXXK][来源:Z+xx+https://www.doczj.com/doc/f613125730.html,] Was it in the street that you met her? Who was it that called him“comrade”? It was not until yesterday that I met my old friend.
重点代词it的用法和练习（含答案） (1)it用做人称代词的用法 it用作代词，意为“它”，既可以指人，也可以指物。it做人称代词，可以用来代替一个名词、短语、从句或句子，以避免他们在句中的重复。这是可以指提到过的，也可以指未提到的，在句中做主语、表语和宾语。 1)指事物，it可以知道除人以外的任何事物或动物。 I dropped my watch and it broke.我把手表掉在地上摔坏了。 2)指人，it主用用于指性别不明的婴儿或只听其声不见其人的人，如： Is it a boy or a girl?是男孩还是女孩？ There is a knock on the door. It must be the postman. “Listen. Someone is crying..”“Oh, it must be Mary.” 3）代替某些代词。 代词it可以用于代替指示代词this, that以及复合不定代词something, anything, nothing等，如：“What’s this?”“It’s a new machine” (2)it用作非人称代词的用法 1)it用作非人称代词主要用来指时间、距离、价值、天气、气温及温度等自然现象。如 It’s too late to go there now.现在去那已经太迟了。 It rained all day yesterday.昨天下了一整天雨。 2)用于某些句型。 It’s time for sth. 该做某事了。 It’s to do sth. 是时候该做某事了。 It’s time for sb to do sth. 某人该干某事了。 It’s (about/high) time +that--从句。某人该做某事了。（从句谓语用过去式，有时候用should+动词原形） It’s first(second)time +that--从句。某人第几次干某事。（从句谓语动词用现在完成时） It’s +时间段+since从句。自从…以来有一段时间了。 It’s +时间段+before 从句。过多长时间才… (3)it用作形式主语的用法。 1)当不定式、动名词、从句等复杂成分做句子主语时，为保持句子的平衡，通常把真正的主语放 在句末，而句首使用形式主语it。如 It’s very important to remember this. It’s hard work climbing mountains. It’s unknown when he will come. 2)it用作形式主语的重要句型。 ①It+be+adj.+for(of)sb to do sth. 某人做某事… It is hard for him to make up his mind.他很难下定决心。 It was foolish of her to say such a thing.她说那样的话，太愚蠢了。 提示：此句型中的介词of和for的区别是：of用于指某人的性格，属性，特征等。介词for表示对象，意为“对…来说”。
定语从句中 which,that 的用法与区别 只能使用that的情况： 1.当先行词是nothing, something, anything, all, each等不定代词时。 e.g. Do you have anything that is important to tell me? 2.当先行词被all, any, some, no, not, every, each等修饰时。 e.g. I have some books that are very good. 3.当先行词被形容词最高级、序数词(包括last, next等)所修饰时。 e.g. This is the first book that I bought mysel f. The biggest bird that I caught is this bird. 4.主句是以which或who开头的特殊疑问句时 e.g. Which is the bike that you lost? 为了避免重复时用that Who is the woman that was praised at the meeting. 5.当先行词在从句和主句中都作表语时,无论先行词是人还是物. China is no longer the country that she was. 6.如有两个定语从句,其中一个已用which引导,另一个宜用that . Edison built up a factory which produced things that had never been seen before. 7.在there be句型中,只用that. He asked for the latest book (that) there is on the subject. 8.当先行词被the very, the last, the next, the only，the same 等词修饰时。 e.g. This is the very book that I lost yesterday. 9.当先行词又有人又有物时。 e.g. I won’t forget the things and the persons that I saw. 10. 先行词被all, every, no, any, little, some, much等修饰时。 I’ve read all the books that are not mine. 只能使用which的情况。 1、非限制性定语从句(即通常用逗号与主句隔开，如果去掉逗号，整个句子仍能表达完整的意义的定语从句)中。 e.g. Mary has a book, which is very precious. 2、在介词之后。 e.g. This is a house in which lives an old man. 3、当主句中的主语被that修饰时。 e.g. That dog which I found in the street belongs to Mary. 4. 非限定性定语从句修饰的是前面的整个句子，而且关系代词和关系副词前面有逗号, 用which开始的定语从句修饰前面半句 e.g. He will wear no clothes, which will distinguish（区分，辨别）him from his fellow men.