关系代词有who，whom，whose，that，which，as等，可用作引导从句的关联词。它们在定语从句中可作主语、表语、宾语、定语等；另一方面它们又代表主句中

为定语从句所修饰的那个名词或代词（通称为先行词）。

如： He is the man whom you have been looking for. 他就是你要找的那个人。

2）关系代词的用法

1.作主语

The boy who is playing ping-pong over there is her brother .在那里打乒乓球的那个男孩是她弟弟。

2）作宾语

This is the an whom I met at the station 这就是我 在车站遇到的那个

3）作定语

He is the fighter whose name is known all over the world.

4 ）作表语

She is no longer the woman that she was.她已经不是过去的他了