定语从句（一）定义及相关术语1．定语从句：修饰某一名词或代词的从句叫定语从句。定语从句一般紧跟在它所修饰的先行词之后。2．先行词：被定语从句修饰的词叫先行词。3．关系词：引导定语从句的词叫关系词。关系词有关系代词和关系副词。关系代词有that, which, who, whom, whose, as 等；关系副词有when, where, why 等。关系词通常有下列三个作用：A、引导定语从句；B、代替先行词；C、在定语从句中担当一个成分。例如： The man who is shaking hands with my father is a policeman. 该句中， who is shaking hands with my father 是定语从句，修饰先行词the man， “who”是引导定语从句的关系词，代替先行词the man，在定语从句中作主语。（二）关系代词引导的定语从句1． who 指人，在定语从句中作主语。The boys who are playing football are from Class One. 正在踢足球的男孩是一班的。Those who want to go to the museum must be at the school gate at 7 tomorrow morning. 想去博物馆的人必须在明晨 7 点到大门口集合。 Yesterday I helped an old man who had lost his way. 昨天我帮助了一位迷路的老人。 That is the teacher who teaches us physics. 那就是教我们物理的老师。2． whom 指人，在定语从句中做宾语，常可省略。 Mr Liu is the person ( whom ) you talked about on the bus. 刘先生就是你们在公共汽车上谈论的那个人。Li Ming is just the boy ( whom ) I want to see. 李明正是我想要见的男孩。 The professor ( whom ) you are waiting for has come. 你正在等的教授已经来了。 The girl ( whom ) the teacher often praises is our monitor. 老师经常表扬的那个女孩是我们的班长。注意：关系代词whom 在口语或非正式文体中常可用who 来代替，也可省略。 The man ( whom / who )you met just now is my old friend. 3． Which 指物，在定语从句中做主语或宾语，做宾语时常可省略。Football is a game which is liked by most boys. 足球是大多数男孩所喜欢的运动。The factory which makes computers is far away from here. 制造计算机的那家公司离这儿很远。He likes to read books which are written by...
