It的特殊用法
一、作形式主语
1．（1）It’s + adj.+ to do sth.
It’s important to study English well.
(2 ) It’s + adj. +that…
It’s important/ necessary/ likely/ possible/ certain/…that…
It’s likely that he will win the game.
It’s certain that he will come this afternoon.
2. It’s + v-ed + that…
(1) It’s said/ thought/ believed/ supposed/ reported/ proved/ known…that…
It’s known that the earth travels round the sun.
= As is known to everybody, the earth travels the sun.
= What is known to everybody is that the earth travels the sun.
(2) It’s suggested/ advised/ proposed/ requested/ required/ insisted/
commanded/ demanded/ ordered/…that…
It’s suggested that she（should）finish her homework this afternoon.
It’s required that I (should) go at once.
3. (1) It’s + 名+that…
常见的名词有：a pity, a fact, an idea, an honor, no wonder等
It’s a pity that he can’t come to the party.
It’s a fact that he didn’t pass the exam.
It’s a good idea that we’ll go outing.
It’s an honor that I was invited to the meeting.
(It’s)no wonder (that) he always takes the first place in the exams.
(2) It’s + 名+doing
常见的名词有：use, good
It’s no use crying.
It’s no good crying over spilt milk.
【谚语】牛奶溢了，哭也没用。

（覆水难收）
4.It + 动+ that…
常见的动词有：happen, seem, matter 等
It happened that I hadn’t money with me.
It seemed that he had known the fact..
Does it matter that he doesn’t come..
二、作形式宾语
1.用于复合结构，可以用一句话“没克服它”来记忆如下六个动词：make,
consider, feel, find, think, take.
He made it clear that he was not interested in English .
He considered it a good idea to go outing with me.
I feel it a great honor to be invited to speak here.
I find it very interesting to study English.
I think it no use arguing with her.
I took it for granted that he would give me some help.
2. 用于表示喜好的动词：like, dislike, hate, appreciate 等。

I hate it when people talk with their mouths full.
I like it in the autumn when the weather is clear.
I’d appreciate it if you would like to teach me how to use the computer.
三、it 的几个特殊结构
1.make it
(1)表示“成功、做到、赶上”
——The train is to leave in five minutes.
——We will never make it.
We can’t make it to the other shore in cold weather.
(2)表示“确定时间”
——When shall we meet?
——Let’s make it next Sunday.
2.as it is
(1)用于句首，表示“事实上”
I thought he would get better, but as it is he is getting worse.
(2) 用于句尾，表示“照原样”
Leave the chair as it is.
3.see (to it) that…注意、留神、负责、保证
See to it that everything is ready.
4.rely on it that…信任、对。

有信心
You may rely on it that she won’t be late.
你可以放心，她不会迟到的。

四、it 的几个特殊句型
1. It is/was + 时间状语+ that…强调句
It was at seven o’clock that I went to work yesterday.
2.(1) It was + 时间点+ when 从句（一般过去时）
(2) It will be + 时间点+ when 从句（一般现在时）
It was 9 o’clock when they arrived at the factory.
【注意】这一句型中的时间只能是表示时间点的名词，前面不能有介词。

It will be July 1 when we meet again.
It is on July 1 that we will meet again.
3.(1) It is/has been + 时间段+since 从句（一般过去时）
It is/has been three years since he joined the army.
(2) It was + 时间段+ since 从句（过去完成时）
It was three days since he had fallen ill.
他生病已经有三天了。

【注意】这一句型since 从句中的谓语动词如果是延续性动词，则翻译成“不做某事多久了”。

It is years since I taught in this school.
我离开这所学校已经几年了。

It is years since I worked in that factory.
我不在那个工厂几年了。

It is years since I lived in this city.
我离开这个城市已经几年了。

It is years since I enjoyed myself so much.
我好几年没玩的这样痛快了。

4.（1）It was + 时间段+before 从句（一般过去时）
It was three days before I knew the result.
(2）It will be + 时间段+ before 从句（一般现在时）
It will be three days before I know the result.
【注意】（1）时态要一致，before 从句只有一般现在时和一般过去时
两种时态。

（2）翻译成“过多久才/就。

”
5. (1) It is the first time + that 从句（现在完成时）
It is the first time that I have spoken in public.
（2）It was the first time + that 从句（过去完成时）
It was the first time that I had spoken in public.
6．It is (high/about ) time + that从句（一般过去时）
It’s time that I went to work.
=It’s time that I should go to work.=It’s time for me to go to work.。