表语从句
系动词后面的从句叫表语从句。
The fact is that … / This is what I want.
要点
- 位于系动词（be、look、seem、become、remain）之后。
- that 引导时一般不能省略。
- whether 可以引导，if 不可以。
- 常与 the reason is that 搭配，注意后面不用 because。
- this is why 与 this is because 方向正相反：It rained hard, and that is why we stayed indoors.（why 后面是结果）／ We stayed indoors, and that is because it rained.（because 后面是原因）—— 前后调错是这一格最主要的一处失分。
- as if / as though 也站在系动词后面：He looks as if he knew everything. —— 说的是现在却用过去式，那层"未必真如此"属虚拟，不是转述退格。
- is 后面若只挂不定式或介词短语，那是表语但不是从句：My plan is to start early. ／ The book is on the desk. —— 判"从句"要看到那里有一套主谓。
例句
He is not what he used to be.
他不再是过去的他了。
The fact is that we have no time.
事实是我们没有时间。
This is where I was born.
这就是我出生的地方。
The question is whether we can finish it today.
问题是我们今天能不能做完。
It rained hard, and that is why we stayed at home.
雨下得很大，所以我们待在家里。
My advice is that everyone should arrive at eight.
我的建议是大家八点都到。
易错提示
- The reason is that… 后面不要再接 because，否则语义重复。
- 表语从句里的 that 一般不省。
- That is because he was late. 这句本身没错，只有前面再套一层 the reason 才算重复 —— 一句里只能有一处"原因"被命名，与老规矩那条合起来看就通了。