it雖然就有兩個字母組成，但它在英語中卻有很大的作用，下面是我學習中總結的it的用法，大家可以參考一下
It的用法
1，作人稱代詞，指一般動物和無生命的東西。
例：The dog is in the garden ，isn’t it?(指前面的名詞)
Where is my pen ？I can’t find it.(指前面的名詞)
She is weak at spoken English and she realized it.（指前面的句子）
He decided to do exercises every morning,but couldn’t keep it up（指前面的句子）
It is difficult to climb a mountain.（作形式主語代替後面的不定式）
It is dangerous playing with fire.（作形式主語代替後面的動名詞短語）
It is a pity that you didn’t see such a good film.(作形式主語代替後面的句子)
It is said that the plane will take off at ten tomorrow morning.(作形式主語代替後面的句子)
She feels it her duty to help others.(作形式賓語代替後面不定式表示的真正賓語)
I thought it no use talking to him about it .(作形式賓語)
They want to make it clear to the public that they do an important and necessary job.
(作形式賓語代替後面的句子)
I think it foolish of you to worry about it .
2,it 作無人稱代詞的用法
What time is it by your watch? It is two thirty.(表時間)
It was some time before he appeared
It’s time for meeting,Let 『s go.
It is very near from this factory to that one.(作主語，表示距離)
It is well with you .(表狀況)
It is rather warm today (表示自然現象，氣候)
3，it用以引導強調句型「It is(was)+被強調部分+that(who)……」
It was I who met your brother at the station yesterday.
It is French that we have been learning these years.
It was with great care that they did the job.
It is the people that\who are really powerful
It was here that I first met him
簡單的 it 這麼多用法，大家掌握了多少？共同學習，共同進步。