4．先行词与关系词的关系

　　(1)关系代词who, that, which实际上是先行词的替代词

　　A plane is a machine that can fly.(that＝a machine)

　　The boy who broke the window is called Tom.(who＝the boy)

　　(2)关系代词whose实际上是先行词的所有格

　　The boy whose parents were dead was brought up by his grandfather.(whose＝the boy's)

　　(3)关系副词实际上是"介词＋先行词"

　　The school where I study is far from my home. (where＝in the school)

　　5．分类

　　(1)限制性定语从句

　　它是先行词在意义上不可缺少的定语，如果去掉，主句的意思就不完整或失去意义。这种从句与主句的关系十分密切，书写时不可用逗号分开。如果关系代词在限制性定语从句中作宾语，关系代词通常可以省略。

　　Do you know the girl who just came in?

　　你认识那个刚刚进来的女孩吗？

　　The time when I first met Mr White was a very difficult period of my life.我第一次遇见怀特先生时是我生命中一个非常艰难的时期。

　　(2)非限制性定语从句

　　它只是对先行词作附加补充说明，如果去掉，主句的意思仍然清楚完整。这种从句与主句的关系不是很密切，书写时往往用逗号分开。非限制性定语从句一般不用that引导。

　　The old woman, who lives on her own, has a cat for company.

　　这个老妇人一个人住，养了一只猫陪伴她。

　　My house, which I bought last year, has got a lovely garden.

　　我去年买的那栋房子有一个漂亮的花园。　

关系代词　 　　

　　[全析考法]

　　Ⅰ.单句语法填空

1．(2018·全国卷Ⅰ)Two of the authors of the review also made a study published in 2014 ________ showed a mere five to 10 minutes a day of running reduced the risk of heart