​​小小it大作用

“It”是英语中的一个好记但不好用的小词，灵活性强、用途广泛，是高考卷中的常客，一般功能有三大类：用作代词、用在强调结构中和用作形式主语及形式宾语，逐一讨论。

一、代词

I 作人称代词

1.指除人以外的一切事物或动物；

I dropped my watch and it broke.

我把手表掉在地上摔坏了。

It's hard work, but I enjoy it.

工作很辛苦，可是我乐意干。

“Where is the dog?”“It’s in the bedroom. ”

 “狗在哪?”“在卧室里”。

2.指人it 指人主要用于指代婴儿，或不清楚对方性别；

The baby is crying. It must be hungry.

婴儿在哭。它一定饿了。

I did not disturb the child because it was sleeping.

我没有打扰那孩子，因为他正在睡觉。

Who is it speaking?

谁打来的电话?

There is a knock on the door. It must be the postman.

有人在敲门，一定是邮递员。

【说明】在答语中，常用来指本人，如说It's me。

3.  代替指示代词this, that 以及复合不定代词 something, anything, nothing等；

“What's this?”“It's a new machine. ” 

“这是什么?”“是一种新机器”。

Nothing is wrong, is it?

没出什么问题，是吗? 

区别: 五个替代词：one, ones, that, those, it 

 ⑴  one 泛指，代替单数名词，可指人或物（同类异物）；

        I need a Chinese-English dictionary, and Peter lends me one.  

我需要一本汉英词典，彼得借给我一本。

one前可加this, that, each、冠词、物主代词或形容词:

        The journalist’s question is a difficult one.

记者的问题有难度。

         I don’t like this one,I’d like a more interesting one.

我不喜欢这本，我想要一本更有趣的。(one:book)

I like the bananas,please give me one more.

我喜欢香蕉，请再给我一个。

Among all people here,Tom is the most humorous one.

这里所有人中，汤姆是最幽默的一个。

⑵ ones是one的复数形式，表泛指，不能单独使用，前面必须有限定词修饰；

These books are easy, but those thick ones are rather difficult.

这些书容易读，但是那些厚的很难读。

There were a few young people with some old ones in the house.

有几个年轻人和一些老年人在那座房子里。(:ones=people)

⑶ that 特指,替代带有of短语的可数名词或不可数名词，替代的是同名异物，不能替代人；   

The population of Beijing is larger than that of Tianjin.

北京的人口比天津的（人口）多。

         The weather in Wuhan is hotter than that of Dongguan.

武汉的天气比东莞的更热。(that : the weather)

(4)those 是 that的复数形式,代替复数名词；

The machines are better than those we produced last year.

这些机器比我们去年生产的要好。(those:the machines=the ones)

(5)it用来替代的是同名同物，可以替代可数和不可数名词，其复数形式是them；

         I lost my pen yesterday and I haven’t found it yet.

昨天我的钢笔丢了，现在还没找到它。

注意：“This is…; That is…”和定语从句搭配的特殊句子：

Is this school the one that you visited yesterday?

这所学校就是你昨天参观的那所吗?

Is this the reason he gave his boss in the office for his carelessness in his work?

这就是他在办公室里向老板解释他工作粗心的原因吗？

The earth looks blue from space. This is because 70% of the surface is covered by water.

从太空看地球是蓝色的。这是因为70% 的表面被水覆盖。

II 作非人称代词

（1）用于指时间、距离、价值、天气、气候及温度等自然现象;

It's too late to go there now.

现在去那儿已经太迟了。

It rained all day yesterday.

昨天下了一天的雨。

It can get very hot here.

这里有时会很热。

It was nearly dark and she was a good fifty miles from home.

天快黑了，她离家还有五十英里。

注意：It was five o’clock when I got home yesterday evening.

: When I got home yesterday evening, it was five o’clock.

昨天晚上我到家的时候已经是五点钟了。

以上句子中it表示时间，不是强调 。对比强调句：

It was at five o’clock yesterday evening that I got home.

 : I got home at five o’clock yesterday evening.

我是在昨天晚上五点钟到家的。

(2)指代前句或后句所述情况

He smokes in bed and I don’t like it. 

他在床上抽烟，我不喜欢他这样。

When the factory closes, it will mean 500 workers will be out of work. 

工厂一旦关闭, 那就意味着要有500工人失业。

(3)用于笼统地谈论某种情况

I cannot help it. 

我也没办法。

(4) 指最好的或最渴望得到事物

He thinks he’s it. 

他一直以为自己是最佳人选。

That steak was really it! 

那牛排真是不错！

We’ve been looking for a house for months and I think this is it. 

我们找房子已经找了好几个月了, 我看这所就是我们要找的。

It would be ideal if you could join us. 

如果你能和我们合作，则太好了。

二、强调句(参考前期公众号文章《it强调句361》《怎么理解what it is》)

It is/was +被强调的成分+ that +余句(即原句中剔除被强调成分后剩下的部分)

(1)强调句型的陈述句式

I met Mary in the street yesterday.

我昨天在街上遇见了玛丽。

It was I who(that) met Mary in the street yesterday.  (强调主语)

It was Mary that(who) I met in the street yesterday.  (强调宾语)

It was in the street that I met Mary yesterday.  (强调地点状语)

It was yesterday that I met Mary in the street.  (强调时间状语)

(2) 强调句型的疑问句式

一般疑问式：Is/Was it that …?

Was it her that you were talking about?你谈到的就是她吗？

特殊疑问式：特殊疑问词+is/was it that …?

Where was it that you saw the man?你到底在哪见过那个男人？

Why is it that you put off the meeting ?你是为什么推迟会议？

(3)强调句型的升级句式

What is it that makes us uniquely human? 

究竟什么使我们人类不同于其他生物的呢？

How is it that you are still here?

 你怎么还在这儿？

It was because he was ill that he didn’t go to school.

正是因为他病了，所以他没有去上学。

Was it Bill, who plays football well, that helped the blind man cross the road?

就是足球踢得好的比尔帮盲人过马路的？

It was in the school, where (or: in which) I once studied, that we held a party.

就是在我曾经就读过的学校我们举办了一场晚会。

Was it in the house, which we visited last year, that the murder happened?

正是在我们去年参观过的那所房子里发生了谋杀案吗？

        It was how the young man had learned five languages that attracted the audience’s interest.

正是这个年轻人如何学会五种语言引起了观众的兴趣。

It is the ability to do the job that matters not where you come from or what you are.

重要的就是做好这份工作的能力，与你来自哪里或者你是什么人无关。

It was not until she took off her dark glasses that I realized she was a famous film star.  

直到她摘下墨镜，我才意识到她是一位著名的电影明星。

: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.  

三、作形式主语

当不定式、动名词、从句等用作主语时，为保持句子结构平衡、上下文衔接、

突出强调、语用功能等，通常在句首使用形式主语it，代指不定式、动名词、从句，

而把真正的主语放在句末。

1)     代指不定式

 (1)It is +adj.+(for sb.) to do sth... ...（某人）做...是...的

　　 常见(形容物的性质)的形容词有：

① important, necessary, natural  important, necessary, natural, easy, safe, common,

normal, hard, difficult, dangerous, unusual, rare, impossible, pleasant...

It is important for her to come to the party.

:For her to come to the party is important.

 她来参加聚会是很重要的。

②necessary, right, strange, natural...

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

:It is important for her to come to the party.

她来参加聚会是很重要的。

(2)a.It takes (sb.) time … to do sth.做…要花费某人(时间)…

How long does it take you to go to Beijing from Qingdao by train?  

从青岛坐火车到北京一般要花多久时间？

b.It takes sth to do... ...做...需要...

It takes great patience to be a good doctor.

做一个好医生需要极大的耐心。

C.what it takes (to do sth)....  (取得成功或达到目的) 所需要的... 

She may not be very gifted but she certainly has what it takes to be a good actress.    

她可能不是很有天赋，但她确实有成为一个优秀女演员所需的素质。

d.It cost sb some time/money to do sth做…要花费某人时间/钱…

       It must cost a good deal to live here.

住这儿一定会花很多钱的。

(3)It is +adj.+(of sb.) to do sth.（某人）做...是...的

　　常见(形容人的特点)的形容词有：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 ...

It is kind of you to say so.

你这样说真是太好了。

: You are kind to say so.

(4)It is up to somebody to do something...由某人决定做某事

It’s up to you to decide how to get there. 

由你决定怎样到那里去。

2)代指动名词

在一些特定句型中被it替代的名词有good,fun,pleasure,use,a waste of time...

　　 　 It is no good learning English without practicing speaking it.

不练习说英语就学不好英语。

:There is no point learning English without practicing speaking it.

It is useless crying over the spilt milk.

覆水难收。

3)代指从句

   代指从句多为that 引导，有时从句中还有虚拟语气的要求。

(1)a. It is clear /obvious/true/ possible/certain(apparent, obvious, true, probable,

likely, possible, impossible, certain… …that ……清楚/显然/真的/肯定…

It is very clear that he's round and tall like a tree.

很明显，他像树一样又圆又高。

　　         :That he's round and tall like a tree is very clear.

        b.It is important/necessary/right/strange/natural…that …(should) do...是重要/必需的...

　　         It is important that we (should) be honest.

重要的是我们要诚实。

　　         It is necessary that he (should) remember these words.

他有必要记住这些话。

(2)It is (generally/commonly/universally)said that …据说/据悉/据报道…

　     常见的动词有：report，learn，believe，admit，acknowledge，agree，announce，

hope，expect，think,consider,know,decided…

It is said that he has come to Beijing.

　　         据说他已经来北京了。

It is reported that another earth satellite has been put into orbit.

据报道，另一颗地球卫星已被送入轨道。

It is announced that they have invented a new type of computer.  

据宣布，他们发明了一种新型电脑。

It is believed that China will become one of the strongest countries in the world.

大家都相信中国将会步入世界强国之列。

(3) It is suggested/ordered /required/recommended…that …(should) do据建议/有命令…

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

　　          有人建议把会议推迟。

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

命令我们两小时内到达那里。

　(4) It is a pity / a shame /a pleasure/a fact/ a wonder…  that …遗憾/开心...的是...

　　 　 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！

(5)It (so/just) happens  that…碰巧

　　 　It happened that the harvest was bad in 1988. 

碰巧1988年的收成很不好。

(6)It seems / appears that ... ... 看来.../似乎...

It seems that he enjoys pop songs very much.

似乎他非常喜欢流行歌曲。

It appears that Tom might change his mind.  

看来汤姆可能会改变主意。

(7)It remains to be seen that ... ...尚不确定；说不准;还有待观察

It remains to be seen who will win.

谁会赢现在尚不能确定。

(8)It matters (a lot) that... ... 很重要...

Does it matter much that they won’t come tomorrow?  

他们明天不来很重要吗?

(9)It makes no difference (to sb.) that... ...不重要；无所谓

It makes no difference to me where you work.

对我来说，你在哪里上班无所谓。

(10) It pays to do sth…    ...是值得/有好处的...

It pays to help others.

帮助别人是值得的。

(11) It turns out that/to be...    事实表明，结果是，原来是

While many thought they heard an explosion, it turned out that

an earthquake occurred.

许多人认为他们听到了爆炸声，但结果是发生了地震。

(12) It can/could be said/argued/seen that...    可以说，可以看出

It can be argued that a lack of foresight got us into this mess in the first place.

可以说，首先是缺乏远见让我们陷入了困境。

(13) It cannot be overstated...    不以为过，毫不夸张

It cannot be overstated that if you are not crystal clear on what you want,

you won’t reach your goals.

毫不夸张地说，如果你不清楚你想要什么，你就不会实现你的目标。

(14) It cannot be denied...    无可否认

It cannot be denied that our current economic and livelihood issues are severe.

不可否认，我们当前的经济和民生问题是严峻的。

(15) It goes without saying...    不言而喻，不言自明，不用说

Kerry will be 80-years old this year, so it goes without saying that if he's going to master the future, he'd better hurry.

克里今年就要80岁高龄了，不用说，要想掌握未来，他得抓紧点了。

(16)It occurred to sb that...想到...

It came to sb. that.../It crowded in on sb. that.../It flashed into sb. that.../

It hit sb. that.../It struck sb.that... 想起...

It suddenly occurred to me that I knew how to solve that problem.

我突然想起我知道怎样解决那个问题。

(17) It makes sense...    有道理，说得通

It makes sense to eat a reasonably balanced diet when slimming.

在减肥过程中保持饮食的营养相对均衡是明智的。

It makes sense that Goebbels constantly described him as a genius.

戈培尔不断地描述他为天才很合理。

(18) (It is) no wonder( that) … 难怪...

It’s no wonder he is not hungry; he has been eating sweets all day.

    难怪他不饿，他整天在吃糖果。

(19)It’s one’s turn to do sth....轮到某人做...

It’s my turn to clean the classroom. 

是轮到我打扫教室的了。

(20) If it were not for…/If it hadn’t been for...要不是...；如若不是...

If it were not for your help, I would still be homeless. 

若不是你帮忙，我现在还是无家可归。

If it hadn’t been for your assistance, we wouldn’t have succeeded.

要不是有你帮忙，我们是不会成功的。

​注意;it/as/what之间的句型转换：

It is known that paper was first made in China.

众所周知，纸最早是在中国制造的。

：As is known, paper was first made in China.

：What is known is that paper was first made in China.

（三）作形式宾语

It作形式宾语的出现有以下四种情形：

① 宾语后有宾语补足语

当不定式、动名词、从句等用作宾语且其后跟有名词或形容词类的宾语补足语时，

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。

常见于动词think, believe, make, find, consider, feel，get,suppose；

I’ve made it a rule never to hurry. 

我已养成凡事从容不迫的习惯。

Do you think it possible to root out crime? 

你认为可以根除犯罪吗?

I think it no use talking nonsense all day doing nothing.

　我认为整天胡说八道无所事事是没有用的。

He found it difficult that climbers breathe at high altitudes. 

他发现登山者在高海拔地区呼吸困难。

②宾语在情感类动词后

表示“喜、怒、哀、乐”的动词,如like, dislike,enjoy, love, hate appreciate, prefer等,

当它们后接从句时，往往不能直接接宾语从句,通常在动词后接it作形式宾语；

I don’t like it that he’s so lazy.

  我不喜欢他那么懒惰。

I hate it when my mother asks me to eat eggs.  

我讨厌母亲要我吃鸡蛋。

I dislike it when you call me “Boss”.

我不喜欢你叫我叫老板。

I hate it when people talk with their mouths full. 我

不喜欢人们嘴里含着饭说话。

We really appreciate it if she offers to help.

如果她来帮忙，我们真的十分感激。 

③that型宾语从句在介词后

that引导的宾语从句不能直接作介词的宾语,就在介词后先接it，再跟that从句;

You may depend on it that we shall always help you.  

尽管放心,我们会随时帮你的。

Would you see to it that she gets home early?  

你负责保证她早到家,好吗?

He insisted on it that he was innocent.  

他坚持说自己是无辜的。

You may depend on it that it is true.

你可以相信这是真的。

I can’t answer for it that he will reply to you as soon as possible.

我不能保证他会尽快给你回信。

④宾语从句过于冗长

由及物动词与介词组成的固定搭配中,宾语从句太长时,须借用it达到整体平衡。

I leave it to your own judgement whether you should do it.  

我让你自己判断这事是否该做。

We owe it to you that there wasn’t a serious accident.  

多亏了你才没有发生严重事故。

He took it for granted that he would easily find a job once he had finished university.

他想当然地认为大学毕业后很容易找到工作。