what开头的定语从句

下面是小编整理的what开头的定语从句，欢迎阅读。

　　什么时候用what引导定语从句

what 不是关系词，所以它不能引导定语从句。但值得注意的是：what 有时相当于“名词(先行词)+关系代词”。关系代词有主语、宾语、定语之分。一般who做主语或宾语whom作为宾语，whose作为定语(whom，whose不可省略)。关系代词在从句中作主语，宾语，定语等，关系副词在从句中作地点状语(where)时间状语(when)，原因状语(why)。例如：

1、他把一切都给了我。

正：He gave me what he had.

正：He gave me everything that he had.

2、这就是你要的东西。

正：This is what you want.

正：This is the thing that you want.

以上实例告诉，what 有时相当于“先行词+关系代词”，同时这也告诉，这样用的 what 前不能再有先行词(即what 不能引导定语从句)。

　　定语从句what和which的区别

what不可以用在定语从句中，定语从句中关系代词用that和which，两者用法上的区别主要为：

可以指人，也可以指物;which只能指物

2.当先行词是不定代词all, something, anything, everything, none, the one等时，只能用that

如： Is there anything that I can do for you?

3.先行词前有形容词的'最高修饰时，要用that

如： This is the best film that I have ever seen for years.

4.先行词前有序数词修饰时，要用that

如： This is the fifth book that I have ever written.

5.先行词前有形容词only, very, few, little等修饰时，要用that

如： She was the only person that was invited to the palace.

6.先行词既指人，又指物时，只能用that

7.在非限制性定语从句中，只能用which

如： She made great progress and won a prize, which gave us a surprise.

8.在介词+关系代词引导的定语从句中，必须用which

如： This is the knife with which John hurt somebody.

9.当先行词本身是that的时候，要用which

如： The predicate is that which is said of the subject.