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。

It is important that we (should) learn English well. It is necessary that he (should) remember these words.

5. It is said (reported, learned....) that ...

该句型中的it 仍是形式主语，真正主语是that 引导的主语从句。该结构常译为＂据说（据报道，据悉．．．）＂。 It is said that he has come to Beijing.

6. It is suggested ( ordered ... ) that ...

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（should + 动词原形），should 可以省。常译为＂据建议；有命令．．

It is suggested that the meeting ( should ) be put off.

It was ordered that we ( should ) arrive there in two hours.

7. It is a pity ( a shame ... ) that ...

该句型中，that后的从句一般用虚拟语气（should + 动词原形），should可省去．表示出乎意料，常译为＂竟然＂。没有这种意义时，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.

8. It is time ( about time ,high time ) that ...

该句型中that 后的从句应该用虚拟语气，值得注意的是① 常用过去时态表示虚拟．② 有时也用should + 动词原形，should 不能省。常译为＂是（正是）．．．的时侯．．．＂。

It is time that children should go to bed. = It is time that children went to bed.

9. It is the first ( second ... ) time that ...

该句型中的 that 从句不用虚拟语气，而用完成时态。至于用什么完成时态，由主句的谓语动词的时态决定。如果是一般现在时，后面从句用现在完成时态；如果是一般过去时，后面从句则用过去完成时态。该结构中 that 可以省去；it有时用 this / that 替换．常译为＂这是某人第几次做某事了＂。

It is the first time I have been here. = This is the first time I have been here.

10 It is the +形容词最高级+ 名词 + that + …..

该句型中的 that 从句不用虚拟语气，而用完成时态。至于用什么完成时态，由主句的谓语动词的时态决定。如果是一般现在时，后面从句用现在完成时态；如果是一般过去时，后面从句则用过去完成时态。该结构中 that 可以省去；it有时用 this / that 替换．常译为＂这是某人做过的最…的事情＂。

This is the best film that I have ever seen . That was the worst song that he had heard .

11. It is .... since ...

该句型主要用作处理瞬间动词的完成时，又要和表示一段时间的时间状语连用的问题。主句中是时间作表语，其时态是现在时或完成时，since 引导的从句通常是一般过去时态，而且是瞬间动词。如果主句是一般过去时，从句则用过去完成时。

It is ( has been ) 5 years since his father died.

12. It is ... when ...

该句型中的 when 引导的是一个时间状语从句，主句中的 it 指时间，表语由具体的时间充当。常译为＂当．．．的时候，是．．．＂。

It was 5 o’clock when he came here.

比较： There was a time when + 定语从句 （曾经一度….； 有一个时期…）

There was a time when Iraq was one of the strongest countries in the world .

There was a time when I was disappointed and wanted to leave here .

13. It be ... before ...

该句型主句中的 it 指时间, 主句中的时态常是将来一般时或过去时两种时态．主句中的表语多是long, not long , 3 days , 2 weeks 等表示时间段的词或短语。常译为＂．．．之后．．．＂。

It was 3 days before he went to Beijing. It will be not long before he finishes his job.

14. It happens (seems, looks, appears ) that...

该句型中it是形式主语，that 引导的是主语从句，主句中的happen , seem等词是不及物动词．

It happened ( so happened ) that he met his teacher in the street. 碰巧．．

It seems that he will be back in a few days. 看来．．．

15. It looks ( seems ) as if ...

该句型中it无意义。 as if 引导一个状语从句。常译为，＂看起来好象．．．＂如果与事实不相符合，则用虚拟语气．

It looks as if he is ill. It looks as if he were ill. It seemed as if he were dying.

16. It takes/costs sb. ... to do sth.

该句型中的不定式是真正的主语，it是形式主语，句型中的直接宾语是时间。常译为＂做．．．要花费某人．．．＂。 It took thousands of people many years to build the Great Wall.

注意： 当主语和表语都是不定式时，不能用it 作形式主语代替动词不定式。

To see is to believe . To respect others is to be respected .

17. It is kind ( of sb. ) to do sth.

该句型中的不定式短语是真正主语，如果不定式的逻辑主语是由 of引起，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： bad , brave , careless, clever , cruel , foolish , good （好心的）, honest , horrible , kind , lazy , modest , naughty , nice（有教养的）, polite, rude , silly , stupid , wise , wrong（错误的）等。 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.

18. It is necessary ( for sb. ) to do sth.

如果不定式的逻辑主语是由for引起，主句中的形容词通常是表示重要性，紧迫性，频繁程度，难易，安全等情况的形容词。常见的形容词有：① important, necessary, natural ② easy , safe , common , normal , hard , difficult , dangerous , unusual, rare , impossible , pleasant等。

在①中的形容词作表语可以用从句改写，

It is important for her to come to the party. = It is important that she (should ) come to the party

19. It is no good / use / fun doing sth.

It is a great pleasure / a waste of time / a bore doing sth .

It is useless / nice / good doing sth .

该句型中的真正主语是动名词或动名词短语，主句中的表语可以是名词或形容词。

It is no good learning English without speaking English. It is useless crying over spilt milk .

20 . It doesn’t matter whether ( if ) ...

该句型中whether(if) 引导的从句是真正主语，该句型常译为 ＂不论（是否）．．．没关系．．．。

It doesn’t matter if they are old.

21. We think it important to learn a foreign language.

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"6123结构"。

6：指主句中常用的动词：think, believe, make, find, consider, feel ( 另外表示人的心理状态的动词还有：like , love , hate , appreciate , don’t mind , depend on 等)

1：指的是形式宾语it；

2：指的是宾补的两种形式：形容词或名词；

3：指的是真正宾语的三种形式：不定式短语，动名词短语或that引导的宾语从句。

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.

I hate it when people talk with their mouths full of food .

I’d appreciate it if you would help me .

I like it when it rains in spring .

 

第二篇：高中英语关于it的用法

it的用法

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？

----It is sixty-three. 六十三元（指价值）

It did not snow much last winter. 去年冬天雪下得不多。（指自然现象）

三、it作引导词

1、作形式主语（formal subject）

当主语是动词不定式短语、动词的-ing形式短语和主语从句时，为了避免头重脚轻，往往把主语放在谓语动词之后，习惯上用it作形式主语来指代后面的真实主语。这个it称为引导词（anticipatory）it，作形式主语，放在谓语动词后的主语是真正的主语。

(1) 代替不定式短语

Is it necessary to complete the design before National Day? 国庆节前完成这个设计有必要么？ In fact, it is a hard job for the police to keep order in an important football match. 事实上，在重要的足球比赛时，警察维持秩序很困难。

It's not easy to finish the work in two days. 两天之内完成这个工作不容易。

It is better to build houses on rock than on sand. 把房屋建在岩石上比建在沙地上要好。 It is necessary to use a short-wave radio. 使用短波收音机很有必要。

It is not a good habit to stay up late. 开夜车不是个好习惯。

（2）代替动词-ing形式短语

It is no use crying over spilt milk. 覆水难收。

It is dangerous walking on thin ice. 在薄冰上行走是危险的。

It won't be any help my going with you. 我跟你去也没什么帮助。

Is it any good trying again? 再试一次有用吗？

（3）代替主语从句

It is a fact that English is being accepted as an international language. 事实上，英语是公认的国际语言。

It is a pity that you didn't go to see the movie. 你没去看这个电影， 真是可惜。

Has it been decided when we are to hold the sports meet? 我们啥时候开运动会决定了没有？ It is known to all that Christopher Columbus discovered America in 1492. 众所周知，克里斯托夫?哥伦布于14xx年发现了美洲。

Does it matter if he can't finish the job on time? 如果他不能按时完成那工作要紧吗？

2、作形式宾语(formal object)

当复合宾语中的宾语是动词不定式、动词-ing形式短语、宾语从句时，往往把宾语放在它的补足语的后面，而把引导词it放在全句谓语动词和宾语补足语的中间。放在宾语补足语后面的宾语叫真正宾语，放在全句谓语动词和宾语补足语中间的引导词it叫形式宾语。

（1）it代替不定式短语

I don't think it possible to master a foreign language without much memory work. 我认为不进行大量的记忆学好英语是不可能的。

He feels it his duty to help others. 他感到帮助别人是他的职责。

She found it very difficult to answer the question. 她发现很难回答这个问题。

People in the west make it a rule to buy Christmas presents for their relatives and friends. 西方国家的人们习惯为他们的亲戚朋友买圣诞礼物。

The little boy found it very interesting to study English. 那小男孩发现学英语很有趣。

(2）it代替动词-ing形式短语

I think it no use telling them. 我认为告诉他们没用。

Do you consider it necessary sending more people over? 你觉得再派一些人去有必要吗？ We think it a waste arguing with him. 我们认为和他争吵是浪费时间。

(3)it代替从句

I hate it when people talk with their mouths full我讨厌人们说话时嘴里吃东西。

They want to make it clear to the public that they do an important and necessary job. 他们想向公众表明，他们所做的工作既重要又有必要。

We think it necessary that we (should) attend the meeting. 我们认为我们去参加那个会议很有必要。

They found it strange that no one would take the money. 他们感到奇怪，谁也不要这笔钱。

四、it用在强调结构中

当我们要强调句子的某一部分（通常总是主语，宾语或状语）时，常用强调结构。其形式为“it is (was)+被强调的部分+who(that)+句子的其它成分”。在这种结构中，it无实际意义，它只帮助改变一个句子的结构，使某一成分受到强调。如I told her the news at the gate yesterday. 这个句子就可借助it改为下列几种形式，各强调一个不同的成分。

1、强调的成分

（1）强调主语

It was I that told her the news at the gate yesterday. 昨天在大门口告诉她这个消息的是我。 It is the ability to do the job that matters not where you come from or what you are.是你的能力很重要，而不是你从哪来或者你是谁。

（2）强调宾语

It was her that I told the news at the gate yesterday. 昨天在大门口我告诉消息的是她。 It was a pen that he bought in the shop yesterday. 他昨天在哪家商店里买的是一支笔。

(3)强调地点状语

It was at the gate that I told her the news yesterday. 我昨天是在大门口告诉她这个消息的。 It was in the bookstore that I met your brother the other day. 前几天我是在书店遇到你哥哥的。

(4)强调时间状语

It was yesterday that I told her the news at the gate. 我是昨天在大门口告诉她这个消息的。 It was not until 1920 that regular radio broadcasts began.直到19xx年才开始正规的收音机广播。 It was not until she took off her dark glasses that I realized that she was a famous film star. 直到她拿下墨镜我才认出她是著名的影星。

It was about 600 years ago that the first clock with a face and an hour hand was made. 早在6xx年前第一座带有表面和时针的钟就造出来了。

2、使用“It is/was…that”强调句型要注意的几点

（1）被强调部分指人时，其后除了用that之外，也可用who或whom。强调的是主语时，使用who；强调的是宾语时，使用whom。

It was Mary who picked up the wallet. 是玛丽拾到了那个钱包。

It was one of my old schoolmates whom I visited yesterday. 我昨天去看的是我的一位老校友。 It was Jack that I met in the park last week. 我上星期在公园遇到的是杰克。

It was her that I met in the park yesterday. 昨天在公园时里我遇到的是她。

(2)强调句的时态

一般说来，原句的谓语动词如果是现在或将来各种时态，则用句型“It is .... that(who, whom) ... 。”如果原句谓语动词是过去各种时态，则用句型“It was ...that(who, whom)....”

It was only when I reread his poems recently that I began to appreciate their beauty. 只是在最近我在读他的诗时才开始欣赏到它的美。

It is Smith who is leaving for Beijing tomorrow. 是史密斯先生明天去北京。

(3)在强调时间、地点、原因或方式状语时，不能用when、where、why或how，只用that。 It was because her mother was ill that she didn't go with us. 就是因为她母亲病了，她才没跟我们一起去。

It was in Shanghai that the Chinese Communist Party was founded on July 1, 1921. 中国共 产 党是在上海于19xx年x月x日建立的。

注意：可用“It is/was because…that…”结构强调because引导的原因状语从句，如上例所示，但不能用该结构强调由since或as引导的原因状语从句，如不能说:It is everybody is here that let's begin our discussion.也不能说: It was as it was raining hard that they had to stay at home.

（4）强调“not...until”结构

在强调“not...until”结构中由until短语（或从句）表示的时间状语时，要用固定的强调句型“It is/was not until ... that ... 。” 其中that从句中的谓语动词用肯定式。

My father did not come until 12 o’clock last night.

= It was not until 12 o'clock last night that my father came home.昨晚直到十二点我父亲才回家。 It was not until his father came in that the boy began to prepare his lessons. 直到她爸爸进来时，那个男孩才开始复习功课。

It was not until she came to see us that we knew her mother was ill in bed. 直到她来看我们时，我才知道她妈妈卧病在床。

（5）在强调一般疑问句中的某一成分时，主句要用一般疑问句的语序。

Did this happen in Guangzhou?

=Was it in Guangzhou that this happened? 此事是在广州发生的吗？

Was it in 1969 that the American astronaut succeeded in landing on the moon？是在19xx年美国宇航员成功登上月球的吗？

（6）特殊疑问句中只有疑问词可以强调，其强调结构是：“疑问词+is/was it +that … ？” When did you get to know her?

=When was it that you got to know her? 你是在什么时候认识她的？

（7）可以强调方式状语和以because引导的原因状语从句。

It was unwillingly that he did it for me. 他是不情愿地替我做的那件事。

It was because he was ill that we had to come back early. 正是因为他病了，我们才不得不早归。

（8）可以强调宾语补足语，当连系动词不是be，表语部分是名词性词组时，也可使用这种结构强调表语，但是，当连系动词是be时，不能强调表语。

It is white that they painted the house. 他们把房子漆成的是白色。（强调宾语补足语） It is a chief engineer that he becomes now. 他现在担任的是总工程师。（强调表语）

（9）强调句的谓语动词除了可采用现在时和过去时的单数形式外，有时根据需要还可采用复杂的形式。

It must have been Mary that you saw just now. 你刚才看到的一定是玛丽。