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. (作定语)
I’m looking at the photograph which you sent me with your letter. (作定语)
With the money that he had saved, he went on with his studies. (作定语)
Do you know the lady who is interviewing our headmaster? (作定语)
