It 做形式主语和形式宾语的句型

常见的It句型（包括it做形式主语和形式宾语）

1.It is/was + 被强调部分+ that/who ... 该句型是强调句型。被强调部分可以是主语，宾语，表语或状语。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。

一般陈述句：Tom bought a book in this bookshop yesterday.

It is Tom who/that bought a book in this bookshop yesterday. 强调主语

It is a book that Tom bought in this bookshop yesterday. 强调宾语

It is in this bookshop that Tom bought a book yesterday. 强调地点状语

It is yesterday that Tom bought a book in this bookshop. 强调时间状语

2. It is 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. 强调句= Not until she took off her dark glasses did I realize she was a famous film star. 倒装句

= I didn't realize she was a famous film star until she took off her dark glasses. 一般句式3. It is+形容词（clear /obvious/true/possible/certain…）+ that 从句该句型中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+形容词（important /necessary/ right/strange/natural...）+that 从句(should) do 该句型和上一个同属一个句型。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 necessary that we (should)learn a foreign language.

注意句型3和4从句中动词的形式

5. It is+过去分词( said, reported, learned…) +that 从句该句型中的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 is studying abroad.

= He is said to be studying abroad.

6. It is+过去分词(suggested ,ordered, required, commanded, advised, proposed, recommended ) +that 从句(should) do 该句型和上一个同属一个句型。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 可以省略。常译为“据建议；有人命令……）”。

It is suggested that you should get up early in the morning.

注意句型5和6从句中动词的形式

7. It is+名词( a pity，a shame，no wonder ... ) +that从句。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.

这种事竟然发生在你们班上，真是遗憾！

It is a pity that he is ill. 他生病了，真遗憾！

8. It is time ( about time , high time ) +that从句该句型中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 you should work hard for you future.

9. It is the first ( second …) time+ that 从句该句型要和上一个句型区别开来。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 替换，常译为“是某人第一（二）次做某事”。

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

10. It is +时间段+ since 从句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。“自从……以来，已经（多长时间了）”

It is three hours since he finished his task.他已经完成任务三小时了。

11. 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 is 1999 when he was born. 当他出生的时候，是1999年。（他出生于1999年）

It is in 1999 that he was born. 他正是在1999年出生的。（强调句结构）

12. It be +时间段+ before从句。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．具体演化为四个句型：(1)It will be+时间段+ before从句。译为“要过……才……”。(2)It won’t be+时间段+ before从句。译为“不要过……就……”。

(3)It was+时间段+ before从句。译为“过了……才……”。(4)It wasn’t +时间段+ before 从句。译为“没过、没要……就……”。

It will be three days/long before he comes back. 要过三天/很久他才回来。

It won’t be three days /long before he comes back. 不要过三天/多久，他就会回来。

It was three days/long before he came back. 过了三天/很久，他才回来。

It was n’t three days /long before he came back. 没过三天/多久，他就回来了。

13. It happens (seems, looks, appears ) that从句该句型中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……

14. It takes/took/will take 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…...花费某人...”

It took him two years to write the book. 写这本书花费了他两年时间。

15. It is no good (use ) doing sth. 该句型中的真正主语是动名词短语，主句中的表语可以是no good , ( not any good ) , no use ( not any use )。常译为“做某事是没有用的/没有好处的”

It’s no use crying for the spoilt milk. 为打翻的牛奶哭泣是没有用的。

16. 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 whether you will come here or not. 你是否来这儿没有关系。

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. 该句型与上一个同属一个句型。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：①important, necessary, natural②easy, 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，如：

It is important for her to come to the party.

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

19. 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 it is going to rain. 看起来天好像要下雨了。（从句用陈述语气）

It looks as if he were a pig. 他看起来像一头猪。（从句用虚拟语气）

it作形式宾语的特殊句型

当不定式、动名词、从句等复杂成分用作宾语且其后跟有宾语补足语时，通常会在宾语补足语前使用形式宾语it，而将真正的宾语移至句末，其基本结构为“动词+it+宾语补足语+不定式(动名词或从句)”。常用动词：find、think、believe、consider等如：

I find it difficult to do the job well. 我发现做好这件事不容易。

I think it best that you should stay here. 我认为你最好住这儿。

We think it no use complaining. 我们认为抱怨是没有用的。

但是，以下几种形式宾语比较特殊，同学们需引起注意（同时它们也是高考的常考考点）：

一、动词+ it + that-从句。如：

I like it that you came. 你来了，我很高兴。

I take it (that) he will come on time. 我认为他会准时来的。

You can put it that it was arranged before. 你可以说这是以前安排的。

Rumor has it that the defense minister will soon resign. 据传闻，国防部长不久就要辞职。说明：能用于此结构的动词不多，常见的有have, take, put, like 等。

二、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。

I’d prefer it if I didn’t have to do so much work. 要是我不必做那么多工作，好就太好了。说明：能用于此结构的动词不多，常见的有enjoy, hate, love, like, dislike, appreciate, prefer等。

三、动词+ 介词+ it + that-从句。如：

See to it that you’re not late again. 注意千万不要再迟到。

Look to it that this doesn’t happen again. 注意不要再发生这种事。

I can’t answer for it that he will come. 我不能保证他会来。

You may rely on it that he’ll come to meet you. 你放心，他会来接你的。

说明：能用于此结构的动词不多，常见的有see to注意到, look to注意到, insist on, stick to, 坚持depend on取决于, answer for为……负责等。

四、动词+ it + 介词短语+ that-从句。如：

I owe it to you that I am still alive. 多亏有你我才仍然活着。

I took it for granted that he would help us. 我认为他会帮助我们的。

说明：能用于此结构的动词不多，常见的有take it for granted认为……理所当然, bring it to one’s attention使人注意……, owe it to sb.把……归功于等。