爱华网人称代词it可以用来代替一个名词、一个短语、一个从句或一个句子，以避免它们在句中的重复。以下是由爱华网小编整理关于代词it的用法，提供给大家参考和了解，希望大家喜欢!
代词it的用法
(一)
it的用法主要体现在以下几个方面：作为人称代词的it，先行代词的it，非人称代词的it以及强调句中的it和it的一些习惯用法。
1. it指代事物、群体、经验、活动等。可以代替一个词、词组或整个句子，以免重复。
That wasn’t where you had dinner，was it?
If you remember these points，it will help you.
When can we come to visit you?Any time you feel like it.
I love running. It keeps me fit.
it也可指代婴孩或性别不详的人。
Do you hear a baby crying?Something must have hurt it.
Who is making so much noise?It must be the children.
Somebody is knocking at the door. I don’t know who it is.
Who is it? 未见具体人，不同于Who is that ?见到具体某人，但不相识。
2. it用作非人称代词的主语，表示气候、天气、温度、时间、地点、距离等或虚指的情境。
It’s Sunday tomorrow.
It’s five miles to the nearest station from here.
It was dull when Tom was away.
It seems that no one would like to help you.
Had it not been for my illness last week，I would have gone with them.
3. it常用作先行代词
代指不定式，可用作形式主语或形式宾语，以it作形式主语或形式宾语的动词有believe，consider，feel，find，imagine，make，regard，suppose，think等。
It is difficult to learn written Chinese.
It is of great help to master a foreign language.
It took me a week to recite the text.
I find it quite necessary to make some changes.
He thought it best to be on his guard.
代指动名词，可作形式主语或形式宾语，常用在下列句型中
It is no good(no use，useless)+动名词
It is a waste+动名词
代指名词性从句，该结构中的名词性从句可用that，when，who等引导。
It happened that they were away.
She wants to make it clear whether you still love her or not.
It is not known what caused the accident.
Has it been found out who is the murderer?
It is believed/known/reported/said/supposed/thought that an egg is the equivalent of one pound of meat. 可转换为An egg is believed/known/reported/said/supposed/thought to be the equivalent of one pound of meat.
另外类似take it one’s duty to do something的结构中，think，find，prove，show，deem，believe，consider，count，feel，imagine，make，regard，suppose，take等词后有不定式作宾语，且有补足语时，必须用形式宾语it代替不定式，若补足语为动名词或从句，也要用it作形式宾语。
I think it my duty to help her.(=It is thought my duty. . .)
I found it very easy to learn the rules.(=It was found very easy. . .)
We shall leave it to him to settle the matter.(=It is left to him to. . . ，
4. 用于强调句型中It is(was)+被强调部分(主语、宾语或状语)+that(who)…。it无任何指代关系，也无实义。
It was John who(that)wore his best suit to the dance last night.
It was in Shanghai that I first met Jack.
It was because I wanted to buy a dictionary that I went to downtown yesterday.
