高中英语巩固练习 it的用法 2

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高中英语It的用法

9. Meeting my uncle after all these years was an unforgettable moment, _____ I will always B treasure. Ａ．that Ｂ．one Ｃ．it Ｄ．What A 10. I prefer a flat in Inverness to ______in Perth, because I want to live near my Mom’s. A. one B. that C. it D. this 11. Cars do cause us some health problems — in B fact far more serious _______ than mobile phones do. A．one B．ones C．it D．those
Grammar It 的用法
1. it 作形式主语,代替不定式、动名词短语或主语从句表示的真正主语： It is hard to deal with him. It is impossible for her to come. It is no good/use waiting here. It is evident that he is lying. It is not clear whether he will go or not. 2. it 作形式宾语,代替不定式、动名词短语或宾语从句表示的真正宾语： I think it easy to repair the radio. I find it hard for her to do the math problems. He felt it no use learning English. I think it necessary that we should take exercise.

高中英语语法权威解析二---“It”用法及其句型和固定搭配讲解(附练习题)

第二章“It”用法及其句型和固定搭配讲解"It" 用法及其句型和固定搭配，是高中英语语法的重点、难点，又是近几年高考的热点，因此应给予充分的重视，现将it用法归纳如下：一、It用作实词表达以下概念:指代前文提到的事物，前文中的this, that；替代前文中的内容；指代一位性别不明的小孩或未知的人；指代未指明但谈话双方都知道的那件事；指代时间、天气、气候、距离等自然现象……二、It用作形式主语替代作主语的从句、动词不定式、动名词，而把真正作主语的从句、动词不定式、动名词置于句尾。

It 作形式主语的常见句型：1. 代作主语的动词不定式，其句型为(1) It be adj. (for sb.) to do sth.此处adj. 通常为描述事件的形容词：easy, difficult, hard, necessary, unnecessary, possible, impossible, likely, unlikely, right, wrong, important, unimportant, legal, illegal, well-mannered, ill-mannered, polite, impolite, clear, obvious, certain, suitable, proper, fit, useful, useless, dangerous…例It is illegal (for a teenager) to drive a car without a license.(2) It be adj. of sb. to do sth.此处adj. 通常为描述人的形容词：kind, unkind, nice, rude, cruel, considerate, thoughtful, thoughtless, careful, careless, silly, foolish, stupid, clever, wise, crazy.例It's kind of you to help me with the problem.(3) It替代作主语的动名词的常见句型It's no good/use doing…It's (well)worth doing…It's (well)worth one's while doing/to do…It's (well)worth while doing/ to do例It's no use crying over spilt milk.2. It替代作主语的从句常见句型(1) It is + noun +从句例It is no secret that the president wants to have a second term at office.(2) It is adj. +clauseIt's surprising that…(should)………竟然……It's a pity/shame that…(should)………竟然……例It's important that you should apologize to her for your rudeness.(=It's of much importance that you should apologize to her for your rudeness.)(3) It verb sb. + clause= It is v-ing + clauseIt+surprise/delight/interest/disappoint/worry/disturb/annoy/amaze/bother/concern/frighten/please/anger sb. that…例It worried me that she drove so fast.(= It was worrying that she drove so fast.)(4) It verb (to sb.) that…= sb/sth verb to do(verb = appear, seem, come about, emerge, follow, chance, happen, occur, transpire, turn out , work out)例It (so) happened/chanced that they were out.(= They happened/chanced to be out.)(5) It is v-ed that…=sb/sth is to do(verb=say, report, think, believe, hope, expect, agree, accept, decide, determine, intend, plan, understand, know）例It is said that the couple have gotten divorced.(=The couple are said to have gotten divorced.)(6) It is v-ed that … (should)…(verb=demand, request, require, order, suggest, advise, recommend例It is suggested that they should begin with the third question.三、It作主语的句型1. It takes sb. …to do…(=sb takes…to do…)某人用多长时间做某事例It took the men a week to mend our roof.(= The men took a week to mend our roof.)2. It's (just)(un)like sb. to do…（不）像某人做某事的风格例It was (just) like him to think of helping us.3. It's (about/high) time that…should /v-ed…是该做某事的时候了例It's(about/high) time that we should take action.4. It's the x-th time (that) …have v-ed…第几次做某事了例It's the third time that he has failed the driving test.5. It is/has been…since …continuous v-ed(延续性动词) 某动作已有多长时间不发生了例It's 10 years that he lived here6. It was(not)…before…过(不)了多长时间某动作发生了例It was not long before they arrived.四、It 作形式宾语用来替代作宾语的从句、动词不定式、动名词，而把真正作宾语的从句、动词不定式、动名词置于句尾。

高中英语语法知识之It的用法总结

高考英语语法知识之It 的用法总结1. It is + 被强调部分+ that ...该句型是强调句型。

将被强调的部分放在前面, 其它部分置于that之后。

被强调部分可以是主语, 宾语, 状语。

强调的主语如果是人, that可以由who换用。

如果把这种句型结构划掉后, 应该是一个完整无缺的句子。

这也是判断强调句型与其它从句的方法。

I.wa.the.tha.(who.cleane.th.classroo.yesterday.I.wa.i.th.stree.tha..me.he.father.2. It was not until + 被强调部分+ that ...该句型也是强调句型。

主要用于强凋时间状语，译成汉语＂直到．．．才．．．＂，可以说.no....unti....的强调形式. It was not until she took off her dark glasses that I realized she was a famous film star.= Not until she took off her dark glasses did I realize she was a famous film star...didn’.realiz.sh.wa..famou.fil.sta.unti.sh.too.of.he.dar.glasses.3. It is clear ( obvious, true, possible,certain....)that .....该句型中it 是形式主语, 真正的主语是that 引导的主语从句, 常译为＂清楚（显然, 真的, 肯定．．．）＂是主语从句最常见的一种结构。

It is very clear that he’s round and tall like a tree.= That he’s round and tall like a tree is very clear.4.I.i.importan..necessary.right.strange.natural....tha....由于主句中的形容词不同, tha.后的从句中要用虚拟语气（shoul..动词原形）, shoul.可以省去。

高中英语人教版浙江专版选修6Unit 4 Section Ⅲ Grammar— it的用法(2) Word版含答案

Section_ⅢGrammar—it的用法(2)语法图解探究发现①There is no doubt that the earth is becoming warmer and that it is human activity that has caused this global warming rather than a random but natural phenomenon.②It was a scientist called Charles Keeling, who made accurate measurements of the amount of carbon dioxide in the atmosphere from 1957 to 1997.③They also agree that it is the burning of more and more fossil fuels that has resulted in this increase in carbon dioxide.④It was during the 20th century that the temperature of the earth went up about one degree Fahrenheit.[我的发现]这些句子都是强调句，句中的黑体词部分标出了句中的强调句结构，即：it_is/was＋被强调部分＋that/who ...句首词用“it”；be动词总是用单数形式，即is或was。

连接词一般用that，当强调部分是人时，强调连接词也可用who。

一、强调句的基本用法强调句就是把句中要强调的部分(通常是主语、宾语、状语或状语从句)放在It is/was和that/who之间，原句中剩余部分放在that/who之后。

1．强调句的陈述句式“It is/was＋被强调部分＋that/who＋其他剩余部分．”The 2022 Winter Olympic Games will take place in Beijing and Zhangjiakou.→It is in Beijing and Zhangjiakou that the 2022 Winter Olympic Games will take place.在北京和张家口将要举行2022年冬季奥运会。

高中英语it作主语的用法专题辅导

号顿市安谧阳光实验学校高中英语it作主语的用法一、具有具体指代作用的作主语的it1. it作主语，可指代上下文提到过的事物或情况，代替前面出现过的单数名词。

如：—Where is my book?—It’s on your desk.2. it作主语，可替代前面出现过的this或that。

如：—What’s that over there?—It’s a temple.3. it作主语，可指代人，常用于说话者揣测心目中不清楚，或未看清楚，或不知其性别的人，尤其是婴儿。

如：—Look. There is a person coming toward us in the distance.—Who is it?(it代替person，不知性别)The baby is crying now. It may be hungry. (it代替baby)—Who is singing outside?—It’s Wang Hua. (it指推测的人)4. it作主语，可表示天气、时间、距离、度量衡以及环境等。

如：It is fine today.What time is it? It’s eight o’clock.It’s a half hour’s ride to our school.It is ten kilometers from the city to our hometown.It was very quiet at that moment.二、具有形式主语作用的it由于主语是由较长的主语从句、不定式短语、动词-ing短语等充当，为了使句子平衡，习惯上把它们放在句末，然后把it放在主语位置上作形式主语。

常见句型有：1. “it+be+形容词+that从句”。

这样的形容词有certain，difficult，easy，funny, important，likely，natural，necessary, obvious，possible，probable，strange，wonderful等。

高考英语It的用法

高考英语It的用法It是高考英语中一个极其重要的词，其用法多样，在不同的语境中具有不同的意义。

下面我们将从it的用法、句型和固定搭配三个方面进行讲解。

一、it用作实词1、表示时间、天气、距离、温度等自然现象。

例如：It is Monday today.今天是星期一。

It is raining outside.外面正在下雨。

It is 5 kilometers away from here.距离这儿有5公里远。

2、表示观点、看法、态度等主观想法。

例如：I think it is a good idea.我认为这是一个好主意。

We think it is important to learn English well.我们认为学好英语很重要。

二、it用作形式主语当不定式、动名词或从句作主语时，为了保持句子结构平衡，避免头重脚轻，常用it作形式主语，代替不定式、动名词或从句，而把真正的主语放在句尾。

例如：It is important to learn English well.学好英语很重要。

It took me an hour to finish the homework.我花了一个小时完成作业。

三、it用作形式宾语当不定式、动名词或从句作宾语时，为了保持句子结构平衡，避免头重脚轻，常用it作形式宾语，代替不定式、动名词或从句，而把真正的宾语放在句尾。

例如：I think it is important to learn English well.我认为学好英语很重要。

He found it hard to learn English well.他发现学好英语很难。

四、it用于强调句型中强调句型是英语中一个重要的句型，用于突出强调某个成分，特别是主语、宾语和状语等。

在强调句型中，it没有实际意义，只是起到引导作用。

例如：It is I who am the best student in my class.我是班里最好的学生。

【高中英语】高中英语语法：It的完整用法

【高中英语】高中英语语法：It的完整用法除了课堂上的学习外，平时的积累与练习也是学生提高成绩的重要途径，本文为大家提供了高中英语语法：it的完整用法，祝大家阅读愉快。

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，就是第三人称单数中性，代表前文已提及过的一件事物。

例如：1)thatvaseisvaluable.it'smorethan200yearsold.那个花瓶很珍贵，它有200多年的历史。

2)iloveswimming.itkeepsmefit.我讨厌游泳，它能够并使我维持身心健康。

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'salovelybaby.isitaboyoragirl?宝宝真可爱，就是男孩还是女孩?it可用来指代团体。

如：it用来替代命令代词this,that.如：5)---what'sthis?---it'sapen.—这是什么?—是一支钢笔。

6)---whosebookisthat?---it'smike's.—那就是谁的书?—就是迈克的。

2.指示代词it，常用以指人。

如：7)goandseewhoitis.回去看一看就是谁。

8)---whoismakingsuchanoise?—是谁发出这样的吵闹声?---itmustbethechildren.—一定就是孩子们。

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)itishalfpastthreenow.现在就是三点半钟。

10)itissixmilestothenearesthospitalfromhere.这里离最近的医院也有六英里。

11)itwasverycold;itsnowedandgrewdark.天气很冷;天下着雪，渐渐地变黑了。

以上就是为大家整理的高中英语语法：it的完备用法，期望同学们写作后会对自己有所协助，预祝大家写作开心。

高中英语语法知识之It的用法总结

高考英语语法知识之It 的用法总结1．It is + 被强调部分 + that ...该句型是强调句型。

将被强调的部分放在前面，其它部分置于that之后。

被强调部分可以是主语，宾语，状语。

强调的主语如果是人，that可以由who换用。

如果把这种句型结构划掉后，应该是一个完整无缺的句子。

这也是判断强调句型与其它从句的方法。

It was they that (who) cleaned the classroom yesterday. It was in the street that I met her father.2．It was not until + 被强调部分 + that ...该句型也是强调句型。

主要用于强凋时间状语，译成汉语＂直到．．．才．．．＂，可以说是 not ... until ... 的强调形式。

It was not until she took off her dark glasses that I realized she was a famous film star.= Not until she took off her dark glasses did I realize she was a famous film star.= I didn’t realize she was a famous film star until she took off her dark glasses.3．It is clear ( obvious, true, possible,certain....) that .....该句型中it 是形式主语，真正的主语是that 引导的主语从句，常译为＂清楚（显然，真的，肯定．．．）＂是主语从句最常见的一种结构。

It is very clear that he’s round and tall like a tree.= That he’s round and tall like a tree is very clear.4. It is important ( necessary, right, strange, natural...) that ...由于主句中的形容词不同，that 后的从句中要用虚拟语气（should + 动词原形），should 可以省去。

高中英语语法it的用法

高中英语it的用法一、代词itA. heB. thatC. itD. theman3. Tom's mother kept telling him that he should work harder, but didn't work.A. heB. whichC. sheD. it4. —How _____ going?— Everything is OK.A. is itB. are theyC. is thatD. arethese5. — He was nearly drowned once.— When was ______ ?— _______ w as in 1998 when he was in middle school.A. that... ItB. this... ThisC. this... ItD. that...ThisKeys:1-5. D C D A A二、引导词it专项练习1. _______ is a fact that Global Warming has influenced human beings' life.A. ThereB. ThisC. ThatD. It2. It is wrong _______ treat your mother like that.A. that you toB. of you toC. for you toD.because you3. Is _______ n ecessary to complete the task before National Day?A. thisB. thatC. itD. he4. Does _____ matter if he can't finish the job on time?A. thisB. thatC. heD. it5. He hasn't had any food for two days. that he is so hungry.A. There is no pointB. There is no needC. It is no wonderD. It is no way6. ______ h e has been fired because of his absence for a long time with no reason.A. It is said thatB. They all said thatC. That is announced thatD. It was reported7. It is no use _____ books without reading.A. to buyB. in buyingC. of buyingD.buying8. _______ h uman beings can live on the moon in the next twenty years.A. There seems impossibleB. This is impossible forC. It is impossible ofD. It seems impossible that9. _______ i n the school regulation that students should wear school uniforms at school.A. What is requiredB. What requiresC. It is requiredD. It requires10. —How do you know him well?— ______that we live in the same neighbourhood.A. It isB. That isC. It is becauseD. Ithappens11. I don't think possible to complete the task without good preparation.A. thisB. thatC. heD. it12. I hate ______ when people talk with their full mouth.A. itB. thatC. theseD. them13. He _______ to do morning exercise in the park.A. took a ruleB. made a ruleC. made it a ruleD. tookit a rule14. I would appreciate _____ you would turn off the TV set.A. thatB. it ifC. these ifD. itthat15. I think _____ hard for you ______ t he task on your own.A. it is... doB. this... to doC. that is... doingD. it...to do16. Don't ______ for granted that he will keep his promise.A. take thatB. take itC. make thatD. makeit17. He soon ______ w hy he had done it.A. spoke clearlyB. made it clearC. told clearD. saidit clear18. Do you think _____ no use ______ another apology to him?A. it... to makeB. it is... makeC. it... makingD. that...of making19. We should regard _____ as a social duty to help these poor and homeless people.A. ourselvesB. theseC. itD. us20. I found ______to watch the football match on TV.A. it relaxingB. that is relaxingC. it relaxedD. thatis relaxedKeys:1-5 DBCDC 6-10 ADD CD11-15 DACBD 16-20 BBCCA三、it在强调结构中专项练习1.It was who telephoned me yesterday.A．him B．his C．himself D．he2. was a handbag that John gave Mary at Christmas.A．It B．This C．That D．Such3.Was the room the famous writer had ever lived in?A．that, it B．it , that C．it , where D．that, which 4.Why is it everyone thinks he’s a thief?A．because B．as C．when D．that5. is known to us Mary dances best.A．She, ×B．It, that C．It, she D．She, who Keys:1-5 AABDBKeys:1-5 DCDDA练习题：单项选择1. _______ that I was watching TV when he came to see me.A. It happenedB. What happenedC. That happenedD. It was happened2. The chairman thought necessary to invite Professor Smith to speak at the meeting.A. thatB. itC. thisD. him3. The Foreign Minister said, " ____ our hope that the two sides will work towards peace."A. This isB. There isC. That isD. Itis4. ______ is reported in the newspaper that the terrible flood has caused a loss of 10 million yuan.A. ItB. ThisC. ThatD. As5. It's up to you whether we should go to the art exhibition right now.A. decidingB. to decideC. of decidingD.decide6. Was ________ that I saw last night at the corner?A. it youB. not youC. youD. thatyourself7. It is about two months James leaves school. He is going to be a lawyer.A. whenB. beforeC. sinceD. that8. ______ turn is ______ to clean the blackboard?A. Which... itB. Whose... itC. Which... thatD.Whose. .. that9. The seriously injured man has stopped breathing. will be no possibility ofmaking him come to life.A. ItB. ThereC. ThatD. This10. Space exploration has been made with the development of modern science.A. it possibleB. it wasC. that being possibleD.possible11. To improve my spoken English, I make to recite a passage of English every day.A. a ruleB. it a ruleC. a rule thatD. arule it is12. He moved to a new flat because is only five minutes' walk from the new flat to his office.A. itB. thisC. thatD.there13. It was _______ several years I had an opportunity of seeing the bird again.A. for... beforeB. not for... thatC. for... whenD. notfor... then14. It was with the greatest difficulty the boy gathered the strength to rise.A. with whichB. thatC. whichD.what15. It is of great help Radio English on Sunday. It is well received.A. to pick upB. of picking upC. to pickD.picking upKeys: 1-5 ABDAB 6-10 ABDBD 11-15 BABBA基础题：一．单项选择：1. It is high time that our child to do some homework.A. learnedB. learnC. will learnD.would learn2. It is essential that every child the same educational opportunity.A. hasB. could haveC. haveD. had3. It was going to be some time he saw his parents again.A. sinceB. untilC. whenD.before4. _______ the 1500's_______ the first European explored the coast of California.A. It is not until... thenB. It was until... thatC. It's not until... whenD. It was not until... that5. I just wonder ________ that made them so depressed.A. why it didB. what they didC. how it wasD.what it was6. It was eight o'clock I got to the school this morning, made our teacher very angry.A. when... thatB. that... thatC. that... whenD.when... which7. ______ , they all went to the lake to swim.A. It was a hot dayB. Being a hot dayC. It being hotD. For it was a hot day8. I don't mind her criticizing me, but is how she does that I object to.A. itB. thatC. thisD.which9. — ______ seems to be something wrong with the machine.—Yes, _____ got a lot of noise.A. It... it'sB. There... it'sC. It... there'sD.There... there's10. ______ a certain doubt among the workers as to the necessity of the work.A. There areB. There isC. They areD. Itis11. Joan had often heard said that Marley had no money.A. oneB. onceC. itD. her12. When you go outing with your sisters, you must see to that they are safe.A. everythingB. itC. thatD.yourself13. He said, " a long way to school. a long way to go yet before we arrive."A. It is... There isB. There is... It isC. There is... There isD. It is... It is14. —Is it my age the boss minds?—I'm afraid not. He will consider necessary to have an experiencedassistant.A. which... itB. that... itC. which... thatD.that... that15. ______ easy to do the repair. All you need is a hammer and some nails.A. You areB. That isC. There isD. ItisKeys:1-5 ACDDD 6-10 DCABB 11-15 CBABD提升题：一、翻译。

人教版高中英语【选修六】[语法讲解 it的用法(2)

人教版高中英语选修六知识点梳理重点题型（常考知识点）巩固练习it的用法（2）概念引入上个单元中，我们已经学习it作代词和形式主语、形式宾语的用法，现在将继续学习it引出强调句的用法及一些与it有关的重点句型。

先看这些句子：1. There is no doubt that the earth is becoming warmer and that it is human activity that has caused this global warming rather than a random but natural phenomenon.2. It was a scientist called Charles Keeling, who made accurate measurement of the amountof carbon dioxide in the atmosphere from 1956 to 1997.3. They also agree that it is the burning of more and more fossil fuels that has resulted in this increase in carbon dioxide.4. It was during the 20th century that the temperature of the earth went up about one degree Fahrenheit.这些句子都是强调句，中的斜体词部分标识出了句中的强调句结构。

用法讲解it引出的强调句1【it的用法----强调句】强调句的结构：It is / was + 被强调部分（主语，宾语，状语）+ that (who / whom) + 其它部分在强调句型中：1. 被强调部分可以是主语、宾语或状语。

2. 引导词一般用that，如果是人的话，强调主语还可以用who，强调宾语用who和whom皆可。

It 的用法

It 及强调句【高考走向】It的用法在高考中是重现率较高的语言点，尤其是it用于强调句。

其考查方式多通过“单项填空”进行，也出现在“完形填空”中。

it的基本用法1.指时间It is nine o’clock now.2.指天气,季节It is fine today.It will be summer in two months’ time.3.指距离It is ten miles from here.How far it is to your office?4.指环境或情况It is too noisy for me to study here.Whose turn is it?例：--- Do you like_______ here?--- Oh, yes. The air, the weather, the way of life. Everything is so nice.A. itB. thisC. theseD. one5.指代婴儿或不知道性别的情况下---Who is knocking at the door?---It’s me.---Who is making such a noise/---It must be the children.6.指上文出现过的同一个事物---There is only a book called《飘》in the opposite shop.---Ok, I’ll buy it at once.注：one, that ,与it的区别：①it = the ( that, this )+名词。

即it是取代前面提到的特定事物。

it是特指，如：I drank some ice tea, but it made me more thirsty.②One = a +名词，即one 代表的是前面提到的同类事物，所以one 所指的名词是不定的。

如：I want a watch, but have no money to buyone.③That = the+名词，即that 所代表的名词和前面所提到的名词属于同一类，但非同一个。

高中英语高考总复习---it用法及强调句型知识讲解及巩固练习题(含答案解析)

高中英语高考总复习---it用法及强调句型知识讲解及巩固练习题（含答案解析）真题再现1.Bach died in1750,but it was not until the early19th century______his musical gift was fully recognized.（2015重庆高考）A.whileB.thoughC.thatD. after2.It was when we were returning home________I realized what a good feeling it was to have helped someone in trouble.（2015湖南高考）A.whichB.thatC.whereD.how3.How would you like______if you were watching your favorite TV program and someone came into the room and just shut it off without asking you?（2015浙江高考）A.themB.oneC.thoseD.it4.If you’re buying today’s paper from the stand,could you get for me?A.oneB.suchC.thisD.that5.Studying Wendy’s menu,I found that many of the items are similar to ____of McDonald’s.A.thoseB.oneC.anyD.all6.No matter where he is,he makes_____a rule to go for a walk before breakfast.A.him B this C.that D.it7.This is not my story,nor______the whole story.My story plays out differently.A.is thereB.there isC.is itD.it is1.C。

高中英语牛津上海版高中二年级第一学期It的用法讲解及练习(有答案)

It的用法讲解及练习1、it可指天气、温度、时间、距离等e.g.—It is cold today, isn’t it?2、用作人称代词，代替前文提到过的事物e.g. The dog is not a cold-blooded animals. It doesn’t need to hibernate.3、为避免重复，it可用来代替前面说过的短语或句子e.g. I tried to persuade my father to give up smoking, but found it impossible.(it=to persuade my father to give up smoking)4、代替指示代词this，thate.g.—What’s this?—It’s an album.—Whose new bike is that?—It’s Mary’s.【注】it与one，that的区别it=the(this, that)+名词，特指并且代替前面所提到的某特定事物。

e.g. He’s bought a new car, so he drives it everywhere to show it off.one=a+名词，one指前面提到的同类事物中的不同的另一个。

e.g. He needs a computer, but he can’t afford one.that=the+名词，that指代的名词与前面的名词属于同一类，但不属同一个。

e.g. The population of China is larger than that of Japan.(注意：that指代population，但其后有一个of短语作定语，以区别于the population of China)【注】it与that的异同it指同一事物，that指同类但并不是同一事物e.g. I like the climate of Kunming more than that of Beijing. The climate of Kunming is mild, and I like it.5、it作形式主语it在句中可作形式主语，而真正作主语的主语从句需要放在句子的末尾。

高中英语it 用作形式主语宾语的用法及24个it句式盘点总结(有习题)

高中英语it 用作形式主语/宾语的用法及24个it句式盘点总结一、用作形式主语当不定式、动名词、从句等用作主语时，避免头重脚轻，通常在句首使用形式主语it，而把真正的主语放在句子末尾。

如：It is stupid to do such a thing. 做这种事真蠢。

It’s no good sitting up too late. 熬夜没有好处。

It is necessary that he should be sent there at once. 有必要马上派他到那里去。

注：类似以下句子中的it也可视为形式主语：It happened that the harvest was bad in 1988. 碰巧1988年的收成很不好。

It seems that she is afraid to tell them about it. 似乎她怕将此事告诉他们。

二、用作形式宾语当不定式、动名词、从句等用作宾语且其后跟有宾语补足语时，就应在宾语补足语前使用形式宾语，而将真正的宾语移至句末。

如：I’ve made it a rule never to hurry. 我已养成凡事从容不迫的习惯。

Do you think it possible to root out crime? 你认为可以根除犯罪吗?He found it difficult to breathe at high altitudes. 他觉得在高空呼吸困难。

注：通常意义的形式宾语主要见于真正宾语为不定式、动名词、从句等且其后跟有宾语补足语时的情形，即用于“动词+it+宾语补足语+真正的宾语”这样的结构，但以下两类形式宾语却比较特殊，其后没有宾语补足语：1. 由于介词后通常不能直接跟that从句作宾语，有个别特殊结构就在介词后先接it作形式宾语，再跟that从句。

如：You may depend on it that it is true. 你可以相信这是真的。

高中英语之it的用法详解

高中英语之it的用法详解首先先讲一下it的用法，然后在出几道题一、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。

—What’s this?—It’s a knife.—Whose watch is that? —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 with 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 night.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。

2017-2018高中英语Unit4GlobalwarmingSectionⅢGrammar-it的用法(2)新人教选修6

三、强调句应注意的问题 1．即使被强调成分是句中的时间状语、地点状语、原因状语等，也不能用when, where, because等而要用that。 It was in front of the bank that the old lady was robbed. 老太太是在银行前面被抢劫的。
2．强调句型中的主谓一致——还原后，由真正的主语来确定谓语动词的形式。
②It was a scientist called Charles Keeling, who made accurate measurements of the amount of carbon dioxide in the atmosphere from 1957 to 1997.
③They also agree that it is the burning of more and more fossil fuels that has resulted in this increase in carbon dioxide.
(2)It was/will be ... before ... “过……就……” It was not/will not be ... before ... “不久……就……”主句中的 it 指时间，表语多是long, not long, three days, two weeks等表示“一段时间”的词或短语。试比较： It was three days before he went to Beijing. 三天后他就去了北京。 It was three days ago that he went to Beijing. 他是三天前去的北京。此句是强调句，去掉“It was ... that”后句子仍然完整合理。