高考重点：It的用法以及含有it的句型
高考英语复习 It的用法讲解
It 的用法一链接高考二主要内容1. 作人称代词或非人称代词2. 指无生命的东西或不详的性别3. 作形式主语4. 作形式宾语5. 用于强调句型中6. 用于几种特殊句式中三练一练一链接高考●主要形式：语法填空、写作等●考点：1. 作人称代词或非人称代词2. 指无生命的东西或不详的性别3. 作形式主语4. 作形式宾语5. 用于强调句型中（时态问题）6. 用于几种特殊句式中（特殊句式用于写作的积累）二·主要内容“It”的用法极其广泛,既可以作人称代词,也可以作非人称代词,表示时间、距离、气候等；既可以充当形式主语和形式宾语,也可以用于强调句结构中;它还常常用在某些动词或特殊词类之后,构成习惯用语。
下面就其使用的重点及难点,分门别类地加以总结。
1. 作人称代词,可以用来代替人、物或事；亦作非人称代词，表示时间、天气、季节、距离等。
It i s r aining c ats a nd d ogs. 雨下得很大。
It is a long way to the college. 大学距这儿很远。
It is eight o’clock sharp now. 现在是8点整。
2. 指无生命的东西，性别不详或性别无关紧要时，可用“It”来指动物，幼童等。
The baby cried because it was hungry。
小宝贝因为饿而哭了。
3. 作形式主语英语中不定式、动名词、主语从句在作主语时，主语往往显得很长，使整个句子看上去有点头重脚轻，这时就需要借助“It”作形式上的主语，而把整个句子的主语移到句子后边去，使句子看上去平稳一些。
It is difficult to study and work at the same time.一边工作一边学习很难。
It is very clear that the elephant's l eg is round a nd tall like a tree.大象的腿跟树干一样圆而高，这点显而易见。
高二英语it的特殊用法知识精讲
高二英语it的特殊用法【本讲主要内容】it的特殊用法：1. it做形式主语或形式宾语2. it在强调句型中【知识总结归纳】在英语中，it可以用做代词〔指人或物〕，做主语指代某些特殊内容，引导一些特殊句型。
〔一〕it在句子中做主语或宾语，指代前面提到的人，动物或事物。
例句：1. He took off his coat and hung it behind the door.2. My uncle has got a dog, and he has had it for five months.3. Don’t think any more about it.4. He bought a new bicycle , but it was stolen two months later. It made him very sad.5. What a beautiful baby! Is it a boy ?6. Who’s that ? It’s me. Please open the door.注意：one 与it的区别，one表示泛指上文中某一个名词所代表的同类事物中的任何一个。
而it特指上文提到的事物本身。
〔二〕it用做句子的主语，表示天气，日期，时间，温度，重量，距离等。
例句：1. It was raining when I left the office.2. It’s February 14th today.3. It’ll soon be breakfast time.4. It 112 miles from London to Birmingham.5. It’s my turn next.〔三〕it用做形式主语或形式宾语：根据句子结构的需要，it用做形式主语或形式宾语，而真正的主语或宾语〔to do 短语，doing短语，名词性从句〕如此放在句尾。
主要句型：It’s +形容词/名词+连词+名词性从句to do sth.doing sth.find / make / think / feel it +形容词/名词+连词+名词性从句to do sth.doing sth.例句：1. It will become more and more important to have a good knowledge of English .2. It’s usual for close friends to have similar ideas and beliefs .3. It’s a pity that I didn’t think of it earlier.4. It’s no use going there so early.5. Out teacher thinks it no good learning without practice.6. Didn’t I make it clear to you that I was not coming ?7. We found it strange that no one would take the money.〔四〕it在强调句型中：在英语中，为了突出强调句子的某一个成分〔谓语除外〕，达到强调或使听话人特别注意这一局部的目的。
it的用法讲解及练习
“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) worthwhile 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。
高考英语语法复习知识It用法
高考英语语法复习知识It用法一、概述小小的it在英语中却扮演着非常重要的角色，它使语言更加生动流畅。
本章将it法分为指代性用法和非指代性用法，对于指代性用法从人称代词和指示代词两方面进行了详尽阐述，将非指代性用法的it分为“虚义”it、“先行”it和“分裂句引导词”it分别予以阐述。
将it用法看作一种分析问题的方法，在具体的语言环境中要能准确判断it的相应用法。
二、分类及用法总的来说，根据it在运用中是否具有指代性，可将it用法分为两大类：一、指代性it，二、非指代性it。
1、指代性it包括：人称代词it、指示代词it。
（1）人称代词代词it一般指物不指人。
如：You shouldn’t hunt the deer and kill it.The cupboard is used to put files on and it is made of steel.但it可指代不知性别的婴儿和小孩。
如：What is it? A boy or girl?His sister gives birth to baby, it is very lovely.it表示鄙视、轻蔑的含义时，也可指人。
如：What a bad and mean man it is.在电话用语中要用人称代词it。
如：Who is it speaking? （而不说who are you speaking?）（2）指示代词①it作为指示代词可以指人，尤其指不知名的人。
如：—Who is knocking at the door?—It is Tom.②it可用于指代名词（或名词短语）和整个句子，既可指代前面已提到的事物或事情，也可指代后面出现的事物或事情。
如：I put my pen in the drawer but now I can’t find it.（it指代pen）—Whose is the car?—It is Mrs. Brown’s.（it指代the car）You have saved my life; I will remember it forever.（it指代第一个分句）Here it is, the walkman you just bought.（it指代walkman）the famous mountain.）There is no any doubt about it, the earth goes around the sun.（it指代后一句the earth goes around the sun）③it也可以指复数名词。
高三英语it的用法
用it起始的句型归纳：
1）it +be+形容词+从句： eg: It is not clear to me why he behaved like that. 2）it +be+名词+从句: eg: It’s a puzzle how life began. 3）it +动词（+宾语）+从句 eg: It doesn’t matter much where we live. eg2: It makes no difference whether we go by train or by boat. 4）it +动词的被动语态+从句 eg: It is not decided who will edit it.
形式主语it
有下面几种类型： Be+形容词+不定式 eg: It’s better to be early. Be+名词+不定式 eg: It was his duty to take care of the orphans. Be+介词短语+不定式 eg: It’s beyond me to say why. It + 及物动词+宾语+不定式 eg: It makes me sick to think about it. Be+名词+动名词 eg:It’s no good standing here in the cold. Be + 形容词+动名词 eg:It’s helpless trying to advise her to do so . 其他结构+动名词 eg:It doesn’t matter waiting a few more days.
it的用法及例句
it的用法及例句It的基本用法全部整理在下面了，大家记得收藏起来，后面经常翻看和识记这些用法，达到熟练运用。
（一）用it作人称代词1）it最基本的用法是人称代词，主要用来表示刚提到的东西以避免重复The car accelerated as it overtook me.那辆汽车一加速就超过了我。
The action of salt on ice causes it to melt.盐作用于冰而使其融化。
I don’t care what a car looks like as long as it gets me from A to B.我到不在乎汽车的样子，只要能把我从一处载到另一处就行了。
I’ve never been there but it is,by all accounts,a lovely place.我从来没去过那个地方，但人们都说那地方很好。
The boat stuck on a sandbank but we soon got it afloat again.小船在沙丘搁浅，没过多久我们就又让它自由行进了。
His book reached an even wider audience when it was filmed for television.他的书拍成电视以后，受众范围更广了。
2）也可代表抽象的事物It was acclaimed as a great discovery.它被誉为一次伟大的发现。
Will you pay cash or should I charge it to your account ? 您愿意付现金还是计入您的账？Communication technologies are far from equal when it comes to conveying the truth.交流的技术在传递事实时差别是很大的。
3）也可指动物或未知性别的婴儿- Is this your dog ?- No,it isn’t.Her baby is due next month,she hopes it will be a boy. 她怀的孩子应该下月出生，她希望是个男孩儿。
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。
高考英语语法之it的用法
2. I hope there are enough glasse for each guest to have ________.(NMET 1995) A.it B.those C.them D.one 解析:答案为D.本题考查替代词it和 one的区别.it用于替代同类的,特定的, 同一的事物;one替代同类的,泛指的 人或物.根据题意"我希望有足够的杯 子使每个客人有一个."可知应用one 泛指enough glasses中的一个.
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 + … 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. It is in a small factory that my brother is going to work.(注意上述各句均为强调句型的"考点") 比较:It is a small factory where my brother is going to work.(定语从句)
(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.
高考英语二轮复习 专题IT的用法
no use/no good/ worth one's while/ a waste of time/ money/energy/ words
2.动词+ it + 形容词 + that从（should）
important/ unimportant/ necessary/ unnecessary /natural/ essential
9. It is adj ( for sb. ) to do sth. important， necessary， natural ， impossible ， unusual ， rare ， normal ， easy ， hard ， difficult ， dangerous ， pleasant ， likely, right, wrong,, , clear, obvious, certain, suitable, proper, useful, 等。
特别注意： it, one和that作替代词的用法及区别 1. it代替前面提到的同一事物,该事物既可以是可数名词也可以是不可数名词。 The news that they failed their driving test upset him, ________? A. did they B. didn\‘t they C. did it D. didn\’t it
高考英语二轮复习之必备语法it的用法、常用句型(共28张PPT)
【说明】能用于此结构的动词不多，常见的 有 have, take, put, like 等
(2) 动词 + it + when (if)-从句。如： I dislike it when you whistle. 我不爱听你吹口哨。 We really appreciate it when she offered to help. 她 来帮忙了，我们十分感激。
四、it用在一些固定表达中 As someone puts it, ... 像某人所说的那样 Please see to it that ... 请务必…… When it comes to ... 当提到……时 It looks / seems as if ... 看起来好像…… It’s time for sth. 该做某事了 It’s time (for sb.) to do sth. (某人)该干某事了 It is (high) time that ... (早就)该……
Mary. I haven’t a dictionary; can you lend me one?
1. how would you like ___D__ if you were watching your favorite tv program and someone came into the room and just shut it off without as you? a. them b. one c. those d. it
五、it与one的区别 两者均可代替前面提到的事物，区别是： it指的是与前面已提到的事物为同一物，此 时的it等于“the +名词”；而one 指的是与 前面已提到的事物为同一类物，此时的one 等于“a +名词”。 e.g. I have a dictionary but I’ve lent it to
【英语】高考必考点：it的固定句式集锦
【英语】高考必考点：it的固定句式集锦第一，it作形式主语的常见句型(1)it替代动词不定式的常见句型为：①It+ be+ adj+ (for sb.) to do sth.此处的形容词通常为描述事件的形容词：easy, difficult, hard, necessary, unnecessary, possible等。
如：It is illegal for a teenager to drive a car without a license.②It +be+ adj.+of sb. to do sth.此处的形容词通常为描述人的形容词：kind, unkind, nice, rude, cruel等。
如：It’s kind of you to help me with the problem.(2)it替代动词-ing的常见句型：It’s no good/use doing...It’s (well) worth doing...如：It’s no use crying over spilt milk.(3)it替代从句的常见句型：①It +be+n.+that从句如：It is no secret that the president wants to have a second term in office.②It +be+adj.（important, necessary, surprising...）+that从句从句中的谓语动词用"should+动词原形"形式，且should可省略。
如：It’s important that you should apologize to her for yourrudeness.③It +v.+sb.+that从句= It +be+ v-ing +that从句如：It worried me that she drove so fast.(= It was worrying that she drove so fast.)④It+v.(+to sb.)+ that从句常用动词或短语有appear, seem, come about, emerge, follow, chance, happen, occur, transpire, turn out, work out等。
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。
英语中it用法全解析
英语中it用法全解析摘要本文主要介绍了英语中it的用法，包括以下几个方面：it作为人称代词，指代前文提到的或语境中明确的人或物。
it作为非人称代词，表示天气、时间、温度、距离等抽象概念。
it作为形式主语或形式宾语，代替不定式、动名词或从句等真正的主语或宾语。
it用于强调句型，突出句子中的某一成分。
it用于其他常见的句式和短语，表达不同的意思和功能。
1. it作为人称代词it作为人称代词，通常指代前文提到的或语境中明确的人或物。
它在句中可以作主语、宾语、定语或表语等。
例如：句子说明He took a quick look at the house and noticed it was veryold.it指代前文提到的house，作主语。
John hates children, and it is difficult to say why.it指代前面提到的事情，作主语。
She made it clear (that) we were not welcome.it作形式宾语，真正的宾语是that引导的从句。
It's me.it作形式主语，真正的主语是me。
2. it作为非人称代词it作为非人称代词，表示天气、时间、温度、距离等抽象概念。
它在句中通常作主语或宾语。
例如：句子说明It is raining.it表示天气，作主语。
It is an hour's walk from my home to the school.it表示距离，作主语。
It is a pity that I didn't think of it earlier.it表示一般情况，作主语。
I don't like it when you are angry.it指代后面的when引导的从句，作宾语。
3. it作为形式主语或形式宾语当不定式、动名词或从句等用作主语或宾语时，为避免头重脚轻或保持句子平衡，通常在句首使用形式主语或形式宾语it，而把真正的主语或宾语置于句尾。
高考英语It句型和强调倒装句式讲解
高考英语It句型和强调倒装句式讲解一、复习思路这三种句式主要在翻译题中考查；每一种句式都是先讲解知识点然后辅以练习，练习难度分为三个层次。
二、复习要点1. 知识点1：It句型"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。
That Sunkong develops fast is well-known to us.______________________________________________________.It作形式主语的概念：当不定式（短语），动名词（短语）或从句在句子中作主语时，为保持平衡，避免句式结构的混乱，常用it 作形式主语，而将真正的主语放在句尾。
It 作形式主语的常用句型:①It + be + 形容词(obvious, true, natural, surprising, good, wonderful, funny, possible, likely, certain, probable, quite clear, unusual, etc.) + that从句。
如：It is certain that she will do well in her exam.It is probable that he told her everything.②It + be + 名词词组(a fact, good news, no wonder, an honor, a good thing, a pity, no surprise, etc.) + that从句。
如：It's a pity that we can't go.It's no surprise that our team should have won the game.③It + be + 过去分词(said, reported, thought, expected, decided, announced, arranged, etc.) + that从句。
高中英语it的基本用法
高中英语it的基本用法''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。
初小内容归纳：一、it指代（后行）作用:1.It的基本用法是用来指代上文所提到的事物。
如橙子妈妈经常给学生用最简单的方法举例：I have a pen and I like it.2.学会区分这几组词：it, that, one, the one, ones, the ones用于指代:橙子妈妈归纳的口诀：it指代同名同物；one指代同名异物, that 指代抽象物体居多即it代替上文提及的原物(复数用they)；one指代上文提及的、泛指的可数名词单数（复数ones）；that指代上文提及的定指的可数名词单数或不可数名词（复数those）, the ones 相当于these, those。
注意：指代不明身份（例如有人在外面叫你或者敲门）或性别的人（如小baby）也用it；指代喜爱的事物或宠物也可用she / he。
A：Who''s it (knocking at the door)? B: It''s me.二、虚义it:（初中阶段的重点内容）虚义it指用作没有具体语义的主语，如表示时间、天气、距离、温度等概念的用法。
It is a good day.It cost me 10 dollars.高中内容归纳一、形式it:由于句子结构的需要，常常把it作形式主语，而把真正的主语放后置。
小伙伴们熟不熟悉！1．形式主语：不定式、动名词以及主语从句作主语时，为避免“头重脚轻”，要将真正的主语后置。
It is obvious that he will win the match. （主语从句作主语）It was worthwhile searching for his ''roots.'' （动名词作主语）It took me 10 dollars to buy the book. （不定式作主语）2．形式宾语：当不定式、动名词、that 从句作宾语，又有自己的宾语补语时，要用it 作形式宾语，而把真正的宾语后置。
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高考重点：It的用法以及含有it的句型英语中it 一词结构看似简单，但其词义广泛，使用范围很广，常令一些初学者感到头痛。
It用法及其句型和固定搭配，是英语语法的重点、难点，又是近几年考试的热点,在高考中也是重现率较高的语言点，其考查方式多通过“单项填空”进行，偶尔也出现在“短文改错”和“完形填空”中。
因此在复习中应给予足够的重视。
下面笔者就it的用法简单归纳如下。
一、代替上文中提到过的人或事物。
指代人时，一般用于小孩或身份不十分明朗的人。
1) －Who is the baby? －It‘s my teacher’s son．2) －Who is that gentleman? －It's my friend Tom．He(不可用It) wants to see you．不定代词one 指代前文提到的同类事物之一，而it 特指上文中提到的同一事物。
试对比：This pair of shoes is small. May I have another one？（泛指的另一双）这又鞋子太小了，再拿一双给我看看好吗My pen is missing.Ican’td find it.我的钢笔丢了找不到了(it指my pen)二. it 作为无人称动词的主语，表示天气，时间，距离，环境情况等等。
这时的it 不指某个具体的东西。
没有明确的含义。
译成汉语可不必译出来。
如1).It‘s half an hour’s walk from here to our school．从这儿到我们学校是步行一个小时的路程2) It‘s nice and warm here．这里非常暖和3) But it's two o'clock now, and it's time for us to go to school．两点了该是上学的时间了4) It’s quite close in the room . Let’s open the window for a while。
房间里太闷，把窗子打开一会儿吧。
三.“It”可以代替指示代记词This ,that .例：---Whose dictionary is that ?---It is mine四,用作形式主语或形式宾语。
1. 当作主语的不定式、－ing短语或从句太长时，往往用it作形式主语，而将真正的主语移至句末，以避免句子头重脚轻。
it作形式主语的常见句型：★it替代动词不定式作主语的常见句型为:1) It is necessary /important /possible/easy…..for sb to do….如:It is necessany to learn a foreign lanuage.学一门外语是有必要的。
It is kind /foolish/polite/brave/careless…of sb to do.常用形容词有:clever/wise/bright/silly/foolish/stupid/kind/cruel/right/wrong等如:It is kind of you to help me=Y ou are kind to help me.:谢谢你帮助我.3)It is up to sb to do sth.该由某人做某事如:It is up to you to decide.由你来决定.4)It is (not)like sb to do sth.做某事是(不)是某人的行为.如:It was not like you to have said such rude words. 说出这样粗鲁的话不像你的行为.5)It is one’s turn to do sth.轮到某人做某事.如;It is your turn to speak 轮到你发言了.6) It takes time to do sth .如:It took me an hour to finish reading the novel.读完这本小说花了我一个小时★It替代动名词作主语的常见句型：It’s no good/use doing…如:It’s no use / good crying over spilt milk．覆水难收It’s (well)worth (one’s )while doing/to dosth.It’s worth（your）while to learn english。
学英语是值得的.★It替代主语从句常见句型:1）It is a pity (a shame ,a fact ,a wonder ,a good thing ,good news etc)that……例如：It is a shame that he didn’t pass the exam.很遗憾他没有通过考试。
2）It is strange(natural surprising obvious true good wonderful possible,impossible,likely,unlikely,quite clear.certain ,etc) that…。
例如：It was quite clear that they had no disire for peace.很清楚他们没有和平的诚意。
3）It seems (happened ,turned out, occurred to sb etc.)that…例如：It seemed that things were not as they expected.看起来情况并不像他们所想象的那样。
4）It is said (reported ,decided ,expected ,arranged ,rumoured ,etc)that …例如：It is said that the tickets have been sold out .据说票已售完。
5) It is time that 从句（谓语用过去时）It is time that he went to school.他本该去上学了.6)It seems/appears/sounds/looksas if…….似乎/听起来/看起来….It seems as if it is going to rain.仿佛要下雨了.2当复合宾语中的宾语是不定式、－ing短语或从句，往往用it作形式宾语，而将真正的宾语移至句末，以使句子重心后移。
Do you think it a good habit to read in bed?你认为在床上看书的习惯吗？We find it difficult to learn English well in such a short time．我们认为很难在这如此短的时间内学好英语I will leave it to you to buy the ticket.我要把买票的事委托给你We think it no use crying over spilt milk．我认为木已成舟哭也没用。
Y ou may depend on it that they will support you.你相信好了，他们会支持你的。
They will answer for it that the computer is reliable.他们愿意保证这台电脑是可靠的。
We made it clear when and where we were going to have the meeting．我们宣布了何时何地要举行会议。
I tookit for granted that you would stay with us .我信以为真你要和我们呆在一起.五.It用于强调结构：it没有具体意义，可强调谓语动词外的成分。
其基本句型为：It+be+被强调部分+that(who)+其它……。
★强调主语：主语是人，一般用who （也可用that ）.其他情况用that.。
强调主语用主格；who或that 后面的句子中谓语动词与被强调的主语在数和人称上应保持一致。
例如：It is I who (that) am to blame应付责任的是我。
It was you who didn’t keep your promise。
是你不遵守诺言It was long overwork that made them get tired.长期超负荷的劳动使他们疲被倦不堪。
★强调宾语：当宾语是指人的名词或代词时、强调句中的连接词用whom或that，其他情况用that。
如：It is you that we have been wanting to visit.我们一直想去访问的是你。
★强调状语：被强调的状语可以是时间状语或地点状语，原因状语。
强调句中的连接词只用that例如：It was at that time that I thought of giring him a call.直到那时我才想起要给他一个电话。
It was in the zoo that they saw the elephants.他们是在动物园见的大象。
在运用it引导的强调句时，要注意以下几点：1）强调句的谓语is或was永远用单数，例如：It was yesterday that I met your father in the street．2）不管被强调部分是哪种状语，只能用that连接，不得使用where、when等连词。
例如：It was in the street that I met your father yesterday．3）被强调部分为人时，可用who(主格)和whom(宾格)代替that，用that也行。
例如：It was your father that/whom I met in the street yesterday．It was I that/who met your father in the street yesterday4）强调句中也要注意主谓一致、人称一致和否定转移的问题。
例如：It is they who are our friends．5）not …untill…句型的强调形式为It is/was not untill that 例如:It was not until ten o'clock that we got home last night．6)as since because 均可引导原因状语从句,但是强调句型中只可以强调because从句例如:It was because he was ill that he didn’t come here.7)注意不要混淆强调句和其他从句。