Period Three　Grammar & Writing

　　表语从句

　　1．定义：在复合句中作表语的从句叫作表语从句。它位于主句的系动词之后，对主语进行解释、说明，使主语的内容具体化。

由从属连词that，whether引导 The question is whether you should ask them for help.

问题是你是否需要向他们求助。

The trouble is that I have never done the work before.

麻烦的是以前我从没做过这个工作。 由连接代词what，who，which引导 Beijing is not what it used to be.

北京不再是过去的样子了。

What she wants to know is which dress she should buy.

她想知道的是应该买哪件衣服。 由连接副词when，where，how，why引导 That is where Lao She used to live.

这就是老舍过去生活的地方。

That is why I didn't pass the exam.

这就是为什么我没通过考试的原因。