代 詞
It 的用法
１．作人稱代詞
John likes playing Pingpong．/ He always does it in the afternoon．(指代上下文提到的事物)；/ It's time we went home. / How far is it from here to your home ? / It is getting warmer and warmer．/ It's very quiet at the moment．(可指時間、天氣、環(huán)境等)
２．引導(dǎo)詞
Ａ．作形式主語，代替由不定式、動名詞或從句表示的真正主語。
It's important for us to learn a second language．/ It's no use talking to him．/ It's known to all that the earth goes round the sun．
B．作形式賓語，代替由不定式、動名詞或從句表示的真正賓語。
We feel it our duty to help others．/ He made it clear that he would leave the city．
C．強調(diào)結(jié)構(gòu)：It is (was) +被強調(diào)部分＋that (或who)…
注意: 在強調(diào)結(jié)構(gòu)中，如被強調(diào)部分為時間狀語或地點狀語，其后的連接詞也絕不能為when 或where，而應(yīng)用that 。在復(fù)習(xí)中，一定要注意句式的不同。
It was in Shanghai that I bought the guitar．(that引起強調(diào)句)
It was Shanghai where I bought the guitar．(where引起定從)
It was twelve o'clock when we arrived there．(when引起時間狀語從句）
It was at twelve o'clock that we arrived there．（that 引起強調(diào)句）
3. it，one，that 的區(qū)別：作為代詞，這三個詞的對比使用是高考的熱點之一。 NMET2000，23．
---Why don't we take a little break? ---Didn't we just have __________?
A．it B．that C．one D．this
NMET2001，25．
The Parkers bought a new house but _________will need a lot of work before they can move in．
A．they B．it C．one D．which
one 用以指代同類事物中的任一，that 特指性強，指代可數(shù)與不可數(shù)詞，而it指代上文提過的同一事物。
不定代詞
不定代詞種類較多，用法各異，在使用中一定要注意區(qū)別。
1、both，either ，neither 都表兩者范圍，在句中作主語、賓語、定語 ，both可用作同位語。 both 意為"兩者都"，either 表"兩者中任一個"，neither表"兩者都不"。
2、any，none ，all 表三者或三者以上范圍，any 表任何一個、一些(不可數(shù)或復(fù)數(shù)概念，用于否定句、疑問句或條件從句中)；none 表三者或三者以上中的哪一個都不；表示不可數(shù)物中的一點兒也沒有；all 整個的；所有的(三者或三者以上)；所有的(不可數(shù))。
e.g.This book is a good seller，so you can buy it at any shop in Beijing．/ None of us are/is perfect．/ All of the village was flooded．
3、no one，nobody，none，nothing：no one，nobody表沒有人，nothing 指沒有什么事物，none 兼指人和物。none 著眼于數(shù)量概念。"特指的人或物一個也沒有，一點兒也沒有"。
----How many people are there in the hall ? ----None．
----who wants to go with him ? ----No one(Nobody)．
----What can you see in the bottle ? ----Nothing．
----Is there any water in it ? ----None．
4、another，the other，the other+復(fù)數(shù)名詞(或the others)，other (或other +復(fù)數(shù)名詞）
It 的用法
１．作人稱代詞
John likes playing Pingpong．/ He always does it in the afternoon．(指代上下文提到的事物)；/ It's time we went home. / How far is it from here to your home ? / It is getting warmer and warmer．/ It's very quiet at the moment．(可指時間、天氣、環(huán)境等)
２．引導(dǎo)詞
Ａ．作形式主語，代替由不定式、動名詞或從句表示的真正主語。
It's important for us to learn a second language．/ It's no use talking to him．/ It's known to all that the earth goes round the sun．
B．作形式賓語，代替由不定式、動名詞或從句表示的真正賓語。
We feel it our duty to help others．/ He made it clear that he would leave the city．
C．強調(diào)結(jié)構(gòu)：It is (was) +被強調(diào)部分＋that (或who)…
注意: 在強調(diào)結(jié)構(gòu)中，如被強調(diào)部分為時間狀語或地點狀語，其后的連接詞也絕不能為when 或where，而應(yīng)用that 。在復(fù)習(xí)中，一定要注意句式的不同。
It was in Shanghai that I bought the guitar．(that引起強調(diào)句)
It was Shanghai where I bought the guitar．(where引起定從)
It was twelve o'clock when we arrived there．(when引起時間狀語從句）
It was at twelve o'clock that we arrived there．（that 引起強調(diào)句）
3. it，one，that 的區(qū)別：作為代詞，這三個詞的對比使用是高考的熱點之一。 NMET2000，23．
---Why don't we take a little break? ---Didn't we just have __________?
A．it B．that C．one D．this
NMET2001，25．
The Parkers bought a new house but _________will need a lot of work before they can move in．
A．they B．it C．one D．which
one 用以指代同類事物中的任一，that 特指性強，指代可數(shù)與不可數(shù)詞，而it指代上文提過的同一事物。
不定代詞
不定代詞種類較多，用法各異，在使用中一定要注意區(qū)別。
1、both，either ，neither 都表兩者范圍，在句中作主語、賓語、定語 ，both可用作同位語。 both 意為"兩者都"，either 表"兩者中任一個"，neither表"兩者都不"。
2、any，none ，all 表三者或三者以上范圍，any 表任何一個、一些(不可數(shù)或復(fù)數(shù)概念，用于否定句、疑問句或條件從句中)；none 表三者或三者以上中的哪一個都不；表示不可數(shù)物中的一點兒也沒有；all 整個的；所有的(三者或三者以上)；所有的(不可數(shù))。
e.g.This book is a good seller，so you can buy it at any shop in Beijing．/ None of us are/is perfect．/ All of the village was flooded．
3、no one，nobody，none，nothing：no one，nobody表沒有人，nothing 指沒有什么事物，none 兼指人和物。none 著眼于數(shù)量概念。"特指的人或物一個也沒有，一點兒也沒有"。
----How many people are there in the hall ? ----None．
----who wants to go with him ? ----No one(Nobody)．
----What can you see in the bottle ? ----Nothing．
----Is there any water in it ? ----None．
4、another，the other，the other+復(fù)數(shù)名詞(或the others)，other (或other +復(fù)數(shù)名詞）