一、考查it用作形式主语的用法

当不定式、动名词、从句等用作主语时，为避免头重脚轻，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’s no good sitting up too late. 熬夜没有好处。

It is quite clear that he has read the book. 很显然，他读过这本书。

It doesn’t matter what he says. 他说什么没关系。

【特别提醒】注意it用作形式主语的三类特殊句式：

1.用作动词look, seem, appear, happen, occur, follow等的主语(后接that从句或as if从句)。如：

It seems that he knows everything. 他好像什么都知道。

It (so) happened that I had no money with me. 碰巧我没带钱。

2.当系表结构后接有if 或when引出的状语从句时，通常在系表结构前使用形式主语表示说话人对某情况的看法。如：

It was a great surprise to me when he did a thing like that. 他这样做使我很吃惊。

It would be a tragedy if anything went wrong. 如果出了什么事就是一个悲剧。

3.用于if it were not for… / if it hadn’t been for…(若不是因为)。如：

If it hadn’t been for the freezing wind they could have reached the injured man in time. 要不是有刺骨的寒风，他们就及时赶到伤员身边了。

二、考查it用作形式宾语的用法

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：

We found it difficult to persuade her. 我们发现很难说服她。

He makes it a rule to get up before dawn. 他习惯于天亮前起床。

I think it very strange that he goes out walking almost every night. 我认为他几乎每晚都出去散步是很奇怪的。

【特别提醒】注意it用作形式宾语的两类特殊句式：

1. 动词+it+if / when从句

当enjoy, like, dislike, love, hate, prefer, appreciate等动词后需要接一个if或when引导的从句时，此时必须要先在动词后接it作形式宾语。如：

She won’t like it if you arrive late. 她不喜欢你迟到。

He hates it when people use his bike. 他讨厌别人用他的自行车。

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，那就太好了。

I would appreciate it very much if you would help me with it. 如果你能帮助我做这事，我会十分感激。

2. 动词+介词+it+that从句

能用于此句型的主要有三个动词，即depend on, answer for, see to。如：

You may depend on it that he will turn up in time. 你可以相信他会及时赶到的。

I can’t answer for it that the boy is honest. 我不能保证这个男孩是诚实的。

I’ll see to it that all these letters will be sent to the post before twelve. 我将注意让所有的信件在12点以前送到邮局。

 

三、考查it在强调句中的用法

强调句的基本结构是：It+be+被强调部分+that(who)+其他部分。如：

It was yesterday that he got married. 他是昨天结婚的。

It was a computer that he bought last week. 他上个星期买的是一台电脑。

【特别提醒】对于强调句的复习要特别注意两种情形：

1.当强调句有插入语或复杂修饰语时：

It was lack of money, not of effort, that defeated their plan. 他们的计划受挫，原因是缺少钱而不是没有尽力。

It was more in sorrow than in anger that he criticized his former colleague. 他批评以前的同事，并非出于气愤而是为他惋惜。

2.当强调句为特殊疑问句时：

Who was it that won the World Cup in 1982? 谁赢得了1982年的世界杯?

How long ago is it that you last saw her? 你上一次看见她是多久以前的事？

四、考查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 (this, that, my...)+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”。比较：

I have a dictionary but I’ve lent it to Mary. 我有一本词典，但我把它借给玛丽了。

I haven’t a dictionary; can you lend me one? 我没有词典，你能借我一本吗?

五、考查it在习语中的用法

包括it的习语很多，比如make it就是其中很重要的一例。如：

You can make it if you hurry. 如果你赶快还可以及时赶到。

He wants to make it as a writer. 他想作一名作家而一举成名。

You needn’t worry; he will make it. 你不必担心，他会办成的。

 

【强化训练】(答案均选it)

1.― I don’t know whether I should go abroad or not, Mum.

― I leave ______ to your own judgment whether you should do it.

A. that                 B. it                    C. this                    D. what

2. In the west, people make ______ a rule to send Christmas present to their relatives and friends.

A. this                 B. that                 C. it                      D.the following

3. Was ______ you who put these books on my desk?

A. it                     B. that                 C. one                   D. who

4. ______ was his nervousness in the interview that probably lost him the job.

A. It                     B. That               C. This                  D. He

5. _______ was what he meant rather than what he said that annoyed me.

A. He                    B. It                   C. Who                  D. What

6. Sales have gone down, and obviously we’d prefer ______ if that didn’t happen.

A. that                   B. this                C. it                       D. which

7. How would you like ______ if someone treated you in that way?

A. this                   B. that                 C. it                      D. him

8. I’d prefer ______ if you didn’t smoke in front of the children.

A. it                      B. that                 C. this                   D. him

9. Men say they like ______ when women make the first move.

A. it                       B. that                 C. this                   D. him

10. I would appreciate ______ if you could let me know in advance whether or not you will be coming.

A. this                    B. that                  C. it                      D. you

11. I like ______ when a book is so good that you can’t put it down.

A. this                    B. it                      C. that                  D. you

12. I don’t like ______ when she tells me how to do things.

A. it                       B. that                   C. her                   D. this

13. “I’d appreciate ______ if you kept quiet about this.” “Don’t worry―your secret’s safe with me.”

A. this                     B. that                  C. it                      D. you

14. Balloons make me nervous―I hate ______ when they burst.

A. this                     B. that                  C. it                      D. them

15. In a way, I would prefer ______ if they didn’t come because it would mean extra work.

A. this                     B. that                   C. it                      D. them