1、 1.it作人称代词作人称代词 1.1.it的最基本用法是作人称代词，主要指刚提到的最基本用法是作人称代词，主要指刚提到 的事物，以避免重复的事物，以避免重复:Ningbo is a beautiful city,isn t it?1.2.也可以指动物或婴儿也可以指动物或婴儿(未知性别的婴儿或孩子未知性别的婴儿或孩子):Is this your dog？No,it isn t.1.3.也可指抽象事物也可指抽象事物:It was a great surprise to me when he did a thing like that 2.非人称代词非人称代词it it有时并不指具体的东西，而泛指
2、天气、时间、环境等，有时并不指具体的东西，而泛指天气、时间、环境等，称为非人称的称为非人称的it：2.1.指天气：指天气：It is a lovely day,isn t it?It is a bit windy.2.2.指时间指时间:It was nearly midnight when she came back.2.3.指环境指环境:It was very quiet in the caf.2.4.指距离：指距离：It is half an hour s walk to the city centre.1.it作人称代词作人称代词 Everyone knows that _ is dan
3、gerous to play with fire,but _ is difficult is to prevent children from playing with fire.A.it,it B.what,what C.it,what D.what,it .引导词引导词it 1.It is+被强调部分被强调部分+that.使用该句型有以下几点请注意：使用该句型有以下几点请注意：强调句的谓语强调句的谓语is或或was永远用单数永远用单数.It was yesterday that I met your father in the street 不管被强调部分是哪种状语，只能用不管被强调部分是
4、哪种状语，只能用that连接，不得使用连接，不得使用where、when等连词等连词.It was in the street that I met your father yesterday 被强调部分为人时，可用被强调部分为人时，可用 who(主格或宾格主格或宾格)和和whom(宾格宾格)代替代替that，用，用that也行。也行。1)It was your father that/whom/who I met in the street yesterday 2)It was I that/who met your father in the street yesterday 强调句中也要
5、注意主谓一致、人称一致和否定转移强调句中也要注意主谓一致、人称一致和否定转移的问题。的问题。It is they who are our friends It was not until ten oclock that we got home last night .it 用作形式主语用作形式主语.1 it代替主语从句代替主语从句 1）It is+adj.+that从句从句 It is clear(obvious，true，possible certain.)that.“清楚（显然，真的，肯定）清楚（显然，真的，肯定）”It is very clear that he s round and
6、tall like a tree.It is important(necessary，right，strange，natural.)that.that 后的从句中要用后的从句中要用虚拟语气虚拟语气（should+动词原形），动词原形），should 可以省去，建议记住该句型中的形容词。可以省去，建议记住该句型中的形容词。It is important that we(should)learn English well.2）.It is+v-ed+that 从句从句 It is said(reported，learned.)that.据说（据报道，据悉）据说（据报道，据悉）“。It is sai
7、d that he has come to Beijing.=He is said to have come to Beijing.It is suggested(ordered /demanded/insisted/commanded.)that.主句中的过去分词是表示请求，建议，命令等词时，主句中的过去分词是表示请求，建议，命令等词时，that 后的从句要用虚拟语气（后的从句要用虚拟语气（should+动词原形），动词原形），should 可以省；常译为可以省；常译为“据建议；有命令）据建议；有命令）It is suggested that the meeting(should)be pu
8、t off.3）.It+n+that.1.It is a pity(a shame.)that.that后的从句一般用虚拟语气（后的从句一般用虚拟语气（should+动词原形），动词原形），should可省去表示出乎意料，常译为可省去表示出乎意料，常译为“竟然竟然”。没有。没有这种意义时，则不用虚拟语气。这种意义时，则不用虚拟语气。It is a pity that such a thing(should)happen in your class.It is a pity that he is ill.2.It is time(about time，high time)that.该句型中该句型
9、中that 后的从句应该用虚拟语气，值得注意的是常后的从句应该用虚拟语气，值得注意的是常用过去时态表示虚拟常译为用过去时态表示虚拟常译为“是（正是）的时是（正是）的时侯侯”/should+原型原型 It is time that children went to bed.It is high time that the children should go to school.3.It is the first(second.)time that.“是第一（二）次是第一（二）次”。该句型中的该句型中的 that 从句用完成时态。如果主句动词从句用完成时态。如果主句动词be是一般现是一般现在时，
10、后面从句用现在完成时态；如果主句动词在时，后面从句用现在完成时态；如果主句动词be是一般过是一般过去时，后面从句则用过去完成时态。该结构中去时，后面从句则用过去完成时态。该结构中 that 可以省去。可以省去。例如：例如：It was the first time that I had been praised.It is the first time I have been here.=This is the first time I have been here.4.It is no wonder that It is no wonder that he didn t want to go
11、.No wonder he didn t want to go.难怪难怪他不愿去。他不愿去。在该句型中如果用肯定形式，表示在该句型中如果用肯定形式，表示“真奇怪，真奇怪，真是令人惊讶真是令人惊讶”；It is a wonder that he reused such a good offer.真奇怪，他拒绝了这样好的帮助。真奇怪，他拒绝了这样好的帮助。4).It+v+that从句从句 It happens(seems，looks，appears)that.该句型中该句型中it是形式主语，是形式主语，that 引导的是主语从句，主引导的是主语从句，主句中的句中的happen，seem等词是不及物
12、动词。等词是不及物动词。It happened(so happened)that he met his teacher in the street.碰巧碰巧.It seems that he will be back in a few days.看看来来 It looks as if he is ill.（真的病了）（真的病了）It looks as if he were ill.（没有生病）（没有生病）It seemed as if he were dying.It doesn t matter whether(if).该句型中该句型中whether(if)引导的从句是真正主语，引导的从句是
13、真正主语，该句型常译为不论（是否）没关该句型常译为不论（是否）没关系。系。It doesn t matter if they are old.2.作形式主语替代不定式作形式主语替代不定式 1).It takes sb.to do sth.做要花费某人做要花费某人 It took thousands of people many years to build the Great Wall.2).It is kind(of sb.)to do sth.主句中的形容词必须是能表示逻辑主语特征的形容词。主句中的形容词必须是能表示逻辑主语特征的形容词。常见的有：常见的有：bad，brave，carele
14、ss，clever，cruel，foolish，stupid，wise wrong等。等。这个句型可以改写为：这个句型可以改写为：sb.is kind to do sth.。It is kind of you to say so.=You are kind to say so.3).It is necessary(for sb.)to do sth.常见的形容词有：常见的形容词有：important，necessary，natural easy，safe，common，normal，hard，difficult,dangerous，等。等。在中的形容词作表语可以用从句改写，在中的形容词作表语可
15、以用从句改写，如：如：It is important for her to come to the party.=It is important that she(should)come to the party.4)It is up to sb.to do sth.It is up to him to clean our classroom today.今天应由他做教室清洁。It is up to parents to teach their children manners.该由父母教孩子礼貌。5)It is one s turn to do sth.It is your turn to
16、clean our classroom today.今天该轮到你做教室清洁。今天该轮到你做教室清洁。.3.作形式主语替代ing形式 It is no good(use)doing sth.该句型中的真正主语是动名词短语，主句中的表该句型中的真正主语是动名词短语，主句中的表语可以是语可以是no good,no use,useless It is no good learning English without writing English.Its useless trying to argue with Shylock.4).It is/was not until.that.It was no
17、t until his mother came back that he turned off the TV.用用It作形式主语的句型：作形式主语的句型：(1)It is adj.to do sth.It is difficult to translate this article.翻译这篇文章翻译这篇文章很难。很难。(2)It is adj.for/of sb.to do sth.It is important for us to learn English.学习英语对我学习英语对我们很重要。们很重要。It s kind of you to help me.你帮助我真是太好了。你帮助我真是太
18、好了。(3)It is up to sb.to do sth.“应由某人负责应由某人负责”或或“是某人的职责是某人的职责”。It s up to you to decide whether to take the job or not.接不接受这份工作由你自己定。接不接受这份工作由你自己定。(4)It is adj.that-clause It is important that we should pay close attention to grain.关注粮食对我们很重要。关注粮食对我们很重要。(5)It is(no)good/use/useless doing sth.It is no
19、 use trying again It is of no use to try again.再试也没用。再试也没用。(6)It is worthwhile doing sth./to do sth.It is worthwhile spending/to spend much time on it.在这件事上花时间是值得的。在这件事上花时间是值得的。(7)It happens that-clause It happened that John was the only witness.碰巧约翰碰巧约翰是唯一的证人。是唯一的证人。(8)It occurs to/strikes sb.that-
20、clause 某人突然想某人突然想到到 It suddenly occurred to/struck me that I hadn t seen Peter all day.我突然想到，我一整天都没看见彼得。我突然想到，我一整天都没看见彼得。(9)It is said/reported/announced/(well)knownthat It is known to us all that he means well.我们都知道他我们都知道他是好意的。是好意的。(10)It takes sb.some time to do sth.It took us one month to complet
21、e this project.我们我们花了一个月完成这项工程。花了一个月完成这项工程。It 作形式宾语作形式宾语.We think it important to learn a foreign language.该句型中的该句型中的it 作形式宾语，为了记忆方便我们可称该句型为作形式宾语，为了记忆方便我们可称该句型为6123结构结构。6指主句中常用的动词：指主句中常用的动词：think,believe,make,find,consider,feel；1指的是形式宾语指的是形式宾语it；2指的是指的是宾补宾补的两种形式：的两种形式：形容词形容词,名词名词,分词。分词。3指的是真正宾语的三种形式
22、：指的是真正宾语的三种形式：不定式短语，动名词短语或从不定式短语，动名词短语或从句。句。We think it our duty to clean our classroom every day.He felt it important learning English well.They found it difficult that they would finish their work in two days.A.sb+v.+it+that从句从句 They found it difficult that they would finish their work in two days
23、.?B.动词动词+it+that从句。常见于从句。常见于like,take,have,put等少数动词之后。等少数动词之后。?I take it that they will succeed sooner or later.（认为，以为；猜想认为，以为；猜想）?我认为他们迟早会成功的。我认为他们迟早会成功的。?The newspapers have it that some Japanese firms have gone bankrupt.?报上说一些日本商号破产了。报上说一些日本商号破产了。(have it 声称声称)?put it?C.动词动词itwhen/if 从句。常见于从句。常见于
24、appreciate,enjoy,like,dislike,love,hate,prefer等少数动词之后。等少数动词之后。?We would much appreciate it if you could do us that favour.?要是你们能帮我们这个忙，我们将非常感激。要是你们能帮我们这个忙，我们将非常感激。?Id prefer it if I didnt have to finish the work.?要是我不必完成那项工作，那就太好了。要是我不必完成那项工作，那就太好了。?d.动词动词+it+过去分词过去分词+从句。常见于几从句。常见于几个可以带过去分词作宾语补足语的动词
25、个可以带过去分词作宾语补足语的动词之后。之后。?I heard it said that that factory was founded in 1995.?我听说那家工厂是我听说那家工厂是1995年创建的。年创建的。?They havent made it known where the meeting is to take place.?他们没有宣布会议在哪里召开。他们没有宣布会议在哪里召开。?e.动词动词+it+介词短语介词短语+that从句。常见于从句。常见于bring it to ones attention;?owe it to sb(归功于归功于);take it for gra
26、nted 等结构中。等结构中。?I owe it to you that I finished my work in time.?多亏有你我才及时完成了工作。多亏有你我才及时完成了工作。?Dont take it for granted that they will support you.?不要想当然地认为他们会支持你。不要想当然地认为他们会支持你。We are counting on it that you will come.该句型中的该句型中的it是一个形式宾语，表示模糊意是一个形式宾语，表示模糊意思或代替后面思或代替后面that 引导的宾语从句。引导的宾语从句。因为在这个句型中的谓语
27、动词都是需要跟宾因为在这个句型中的谓语动词都是需要跟宾语的，但又不能直接跟从句作宾语，于是就语的，但又不能直接跟从句作宾语，于是就得在从句前加上一个形式宾语得在从句前加上一个形式宾语it。常见的短语和动词有：常见的短语和动词有：count on(依靠，依靠，指望，期盼指望，期盼),see to(负责负责),depend on(依依靠靠),rely on(信赖，依靠信赖，依靠)等。等。See to it that 注意注意,务必务必,保证保证 find possible 1.S+think +it +necessary +(for sb.)to do sth./that feel importa
28、nt 除了替代从句，除了替代从句，it还可以替代不还可以替代不定式和定式和ing形式形式 a rule 2.S+V +it +one s duty +(for sb.)to do sth./that an honour 3.S +V+it +no good +doing sth.no use We think it our duty to clean our classroom every day.He felt it no good playing computer games.They found it difficult that they would finish their work
29、 in two days.It作形式宾语的句型作形式宾语的句型:(1)主语主语vt.(think/consider/feel/suppose/believe etc.)it adj to do sth.I found it difficult to explain to him what happened.我我觉得向他解释清发生了什么事很困难。觉得向他解释清发生了什么事很困难。(2)主语主语vt.it useful/useless/no good/no use doing sth.He thought it no use going over the subject again.他认他认为再讨
30、论这个问题没有用了。为再讨论这个问题没有用了。(3)主语主语vt.itadj.that-clause He didn t make it clear when and where the meeting would be held.他没有明确说明会议在什么时间、什么地他没有明确说明会议在什么时间、什么地点举行。点举行。(5)see to it that务必使务必使，保证使，保证使 Will you see to it that the luggage is brought back?你你能保证行李会被拿回来吗？能保证行李会被拿回来吗？(6)表示喜欢，恨等心理方面的动词如表示喜欢，恨等心理方面的
31、动词如:like,love,hate,appreciate,dislike等后加上等后加上it作形式宾语，再加上作形式宾语，再加上that/if/wh-从句作真正宾语。（详细解释见下）从句作真正宾语。（详细解释见下）I d appreciate it if you would like to teach me how to use the computer.如果你愿意教我如何用电脑我将不胜如果你愿意教我如何用电脑我将不胜感激。感激。I hate it when people talk with their mouths full.?但我们常会碰到但我们常会碰到it用作形式宾语时之后没用作形式宾
32、语时之后没有形容词或名词作宾语补足语的情况，这有形容词或名词作宾语补足语的情况，这一点在近几年高考试题中经常涉及，需引一点在近几年高考试题中经常涉及，需引起同学们的注意。起同学们的注意。?I hate_ when people talk with their mouths full.(NMET 1998)?A.it B.that C.these D.them (答案为答案为:A)我讨厌人们一边吃饭一边说话。我讨厌人们一边吃饭一边说话。?I like _ in the autumn when the weather is clear and bright.(全国卷全国卷 2004)?A.this
33、 B.that C.it D.one (答案为答案为:C)?我喜欢秋天晴朗的天气。我喜欢秋天晴朗的天气。?以上这两道高考题中，以上这两道高考题中，it用作形式宾语，它用作形式宾语，它的真正的宾语则是由的真正的宾语则是由when引导的从句。引导的从句。“it”的这种特殊用法常出现在以下几种结的这种特殊用法常出现在以下几种结构中。构中。?理解了上述几种情形，不妨完成下列巩固练习：理解了上述几种情形，不妨完成下列巩固练习：【答案在下方】【答案在下方】?1.I would appreciate it_ you call back this afternoon for the doctors appoi
34、ntment.（上海（上海卷卷 2003）?A.until B.if C.when D.that?2.I dont think_ possible to master a foreign language without much work.(MET 1990)?A.this B.that C.its D.it?3.We all took _ for granted that he would agree with us.(MET 1987)?A.it B.him C.that D.what?4._ that you are not late for school again.?A.See t
35、o B.Look to C.See to it D.Look it to?5.Ive often_ that he has great concern for his comrades.?A.heard it said B.heard said C.heard said it D.heard it say?6.Why dont you bring _ to his attention that you are too ill to go on working?A.this B.you C.him D.it?参考答案：参考答案：1.B 2.D 3.A 4.C 5.A 6.D Special no
36、tice:Special notice:it be“是是”vsthere be “有有”It is?There is?There is 1._ someone at the door.I think _ it is the man to deliver the milk.There is 2.Lets hurry!_ a long way to go.3._ no need to hurry.We still get much There is time.4._ a wonder that he refuses such a good It is offer.There is 5._ no d
37、oubt that he has done something bad.6._ no possibility that he will cheat us.There is 7._ no good arguing with the unreasonable It is woman.8._ no difference between the two plans.There is 9._ was a time when 10._ is no denying that 11._ is a chance that 12_used to be a tree in the house.13._ goes w
38、ithout saying that不言而喻 14._ occurred to sb that 15._ is convenient to sb.16.When _ comes to football,I am worse.17._ turned out that 18._ hadnt been for the exams,I would have been there.1.(2005,全国全国)The doctor advised Vesa strongly that she should take a holiday,but _ didn t help.A.it B.she C.which
39、 D.he 正确答案：正确答案：A。根据句意：医生的建议未起作用。根据句意：医生的建议未起作用。it代替整个句子。代替整个句子。2.(2004,全国全国)-Do you like_here?-Oh,yes.The air,the weather,the way of life.Everything is nice.A.this B.these C.that D.It 正确答案：正确答案：D。根据下文，提问者不能确定被问者喜欢什么，。根据下文，提问者不能确定被问者喜欢什么，it用用于不确定指代或模糊指代。于不确定指代或模糊指代。3.(2000,上海上海)Someone is ringing th
40、e doorbell.Go and see_.A.who is he B.who he is C.who is it D.who it is 正确答案：正确答案：D。说话时，不知道对方的性别。注意在宾语从句中。说话时，不知道对方的性别。注意在宾语从句中需用陈述语序。需用陈述语序。4.(2007,全国全国)Have you heard the latest news?No,what _?A.is it B.is there C.are they D.are those 正确答案：正确答案：A。it指代上文提及的指代上文提及的latest news。6.(2002,北京北京)-He was nea
41、rly drowned once.-When was _?-_ was in 1998 when he was in Middle School.A.that,It B.this,This C.this,It D.that,This 正确答案：正确答案：A。it指时间。指时间。8.（2005，江苏），江苏）I m moving to the countryside because the air there is much fresher than _ in the city.A.ones B.one C.that D.those 正确答案：正确答案：C。分析语境和逻辑关系可以知道：该空指代。
42、分析语境和逻辑关系可以知道：该空指代the air，且有且有in the city后置定语修饰。后置定语修饰。9.(2004,北京北京)The Foreign Minister said,“_ our hope that the two sides will work towards peace.A、This is B、There is C、That is D、It is 正确答案：正确答案：D由句意易知：由句意易知：that从句是真正的主语从句是真正的主语;it为形式主语。为形式主语。12.(2006,全国全国)It is no _ arguing with Bill because he
43、will never change his mind.A.use B.help C.time D.way 分析：正确答案：分析：正确答案：A。为固定结构。为固定结构。13.(2007,天津天津)He didn t make _ clear when and where the meeting would be held.A.this B.that C.it D.these 正确答案：正确答案：C。it为形式宾语，为形式宾语，clear后的从句为真正的宾语。后的从句为真正的宾语。14.(2006,湖南湖南)As the busiest woman in Norton,she made _ her
44、 duty to look after all the other people s affairs in that town.A.this B.that C.one D.it 正确答案：正确答案：D。真正宾语为不定式。真正宾语为不定式。16、(2004,全国全国)I like _ in the autumn when the weather is clear and bright.A、this B、that C、it D、one 正确答案：正确答案：C。love/enjoy/hate和和like的用法相的用法相同，后接宾语从句时需用同，后接宾语从句时需用 it作形式宾语，宾语作形式宾语，宾语
45、从句后置。从句后置。17、(2003,上海上海)I would appreciate it _ you call back this afternoon for the doctor s appointment.A、until B、if C、when D、that 正确答案：正确答案：B。18.(1998，上海，上海)Don t _ that all those who get good grades in the entrance examination will prove to be most successful.A.take as granted B.take this for gr
46、anted C.take that for granted D.take it for granted 正确答案：正确答案：D。take it for granted that 意为：想当然的认为某意为：想当然的认为某事。事。it为形式宾语，真正的宾语为为形式宾语，真正的宾语为 that从句。另外我们也应该注从句。另外我们也应该注意：意：depend(rely)on it（相信某事）和（相信某事）和see to it（负责某事）的（负责某事）的用法。用法。33、(2008,北京北京)I m sorry you ve been waiting so long,butit ll still be
47、some time _ Brian gets back.A.before B.since C.till D.after 正确答案：正确答案：A。It be+时间时间+before 表示过了一段时间才表示过了一段时间才 34.(2006,福建福建)How long do you think it will be _ Chinasends a manned spaceship to the moon?-Perhaps two or three years.A.when B.until C.that D.before 正确答案：正确答案：D 35、(2005,安徽安徽)That was really
48、 a splendid evening.It s years _ I enjoyed myself so much.正确答案：正确答案：D。A.when B.that C.before D.since 38.(2005,安徽安徽)-Shall we go to the art exhibition right away?-_.A.It s your opinion B.I don t mind C.It all up to you D.That s your decision 39、(2006,湖北湖北)You know who came yesterday?-Yao Ming?We had
49、seen basketball match.-_ He came and watched the game.A.You guessed it!B.How did you know that?C.Well done!D.That was good news!正确答案：正确答案：A。由具体语境易做出正确选择。由具体语境易做出正确选择。40.(2008,天津天津)How much do I own you for lunch?-_.It s nothing.A.You re welcome B.Forget it C.With pleasure D.That s all right 正确答案：正确答案：B。
