六、相互代词

     表示相互关系的代词叫做相互代词。相互代词有 each other 和 one another 两种形 式。在当代英语中， each other 和 one another 没有什么区别。相互代词可在句中作宾语，定语。作定语用时，相互代词用所有格形式。
We should learn from each other / one another. （作宾语）
Do you often write to each other / one another? （作宾语）
We often borrow each other's / one another's books. （作定语）
The students corrected each other's / one another's mistakes in their homework.（作定语）

七、疑问代词

     疑问代词有 who ， whom ， whose ， what 和 which 等。疑问代词用于特殊疑问句中，一般都放在句首，并在句子中作为某一句子成分。例如：
Who is going to come here tomorrow? （作主语）
What is that? ( 作表语 )
Whose umbrella is this? ( 作定语 )
Whom are you waiting for? ( 作宾语 )

八、关系代词

     关系代词是一种引导从句并起连接主句和从句作用的代词。关系代词有 who, whose, whom, that, which. 它们在句中可用作主语 , 表语 , 宾语 , 定语 . 在主句中 , 它们还代表着从句所修饰的那个名词或代词。例如：
I hate people who talk much but do little.
I'm looking at the photograph which you sent me with your letter.
With the money that he had saved, he went on with his studies.
Do you know the lady who is interviewing our headmaster?