【原】表语从句的用法大全

一、何谓“表语”？

说到表语从句，就不得不先说说什么是“表语”。

表语是英语区别于汉语所特有的一种词类，是起表述作用的句子成分：

从形式上讲，它是位于系动词之后的成分；

从含义上讲，它是用来描述主语“是什么或是怎么样”的成分。

表语是用来说明主语的身份、性质、品性、特征和状态的。表语必须和系动词一起构成系表结构，作为句子的复合谓语。表语通常由名词、形容词、介词短语、不定式、形容词化的现在分词或过去分词以及从句来充当。

二、何谓“表语从句”？

当句子的表语由从句来充当时，这个从句就叫做表语从句。

表语从句一般都是位于系动词之后的。

三、表语从句的连接词

常用来引导表语从句的连接词主要有：

• that

• whether

• what/who/whom/whose/which

• when/where/why/how及其短语
  

（一）that

当that引导表语从句时，只起连接作用，不在表语从句中充当任何句子成分。如：

• His advice is that we should leave for Shanghai before dawn.
  

• Her plan is that she will call the police first and then try to stop the thief from running away.

【注意】

当名词主语是表示建议、命令、要求等含义（如advice、order、idea、notion、proposal、suggestion、request等）时，其表语从句中的谓语动词一般要采用“should+do”的形式，should可以省略。如：

• The officer's order was that all the soldiers (should) never surrender to the enemy.

（二）whether

当表语从句要表达“是否”的含义时，连接词要用whether。如：

• His question is whether they can arrive in London on time.

需要注意的是，尽管if也可以表示“是否”的含义，但在表语从句中只能用whether，不能用if。

（三）what/who/whom/whose/which

这些疑问代词如果用来连接表语从句，既起着连接作用，同时又在从句中充当句子成分，可以作主语、宾语、定语等。如：

• My concern is what he really expects to get from us.

• Her question is who has broken the glass.

• Our dilemma is which side we should take.

• Their worry is whom she can rely on.

• His puzzle is whose money it belongs to.

（四）when/where/why/how及其短语

这些疑问副词如果用来连接表语从句，既起着连接作用，同时又在从句中充当句子成分，一般作状语。如：

• The question is when he will show up at the party tomorrow.

• He remains where I was last night.

• That's why he was late for school this morning.

• Her concern is how he managed to climb into her kitchen yesterday.

【注意】

当主语是reason时，表语从句要用that连接，而不是because。如：

The reason why he was late was that he missed the first morning bus.

四、表语从句的特殊连接词

除了以上常见的连接词外，还有一些特殊的连接词可以用来连接表语从句。

（一）(just) as

表示“正如”，经常与表象系动词look/seem/appear搭配使用。如：

• She looks just as she was ten years ago.

（二）as if/though

表示“好像”，也常与表象系动词look/seem/appear搭配使用。如：

It looks as if/though it's going to rain soon.

【注意】

这种情况下，as if/though后面的表语从句中的谓语动词一般采用虚拟语气形式，其用法是：该谓语动词的时态要采用相应的过去时态。如：

• She acts as if/though she were the hostess of this house.

• They looked as if/though they had lived here for a long time.

（三）because

前面讲到why可以用来连接表语从句，其实because也可以用来连接表语从句。如：

• She is very familiar with the film. This is because she has already seen the film.

【注意】

在这种情况下，尽管since/for/as都可以表示原因，但这三个词不能用来连接表语从句。

五、小测试

好了，接下来大家来做一做下面的6道真题，看看你能做对几题：

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