名词性从句

第十九章名词性从句

本章重点、难点：对名词性关系从句和名词性疑问从句的理解，名词性从句作宾语的

各种情况。

19.1 概述

名词性从句是指一个分句在句子中相当于名词充当主语、宾语、表语、同位语等。这种分句通常由从属连词that、whether（if）引导，也可由连接代词what, whatever, which, whichever, who, whoever, whom, whose等引导，还可以由连接副词where, when, how, why等引导。

19.2 主语从句

主语从句是指一个分句充当句子的主语，它可以由that, what, whatever, who, whoever, when, where, how, why, whether等引导。

19.2.1 由that引导的主语从句

主语从句是陈述事实的时候，从句用that引导。that在从句中没有作任何成分，只起连接作用。在大多数情况下，为了保持句子平衡，从句用形式主语it代替，把that从句放到句子后面，尤其句子是主系表结构的时候。如：

It is impossible that he should come over himself.

It’s strange that he should have left without saying“goodbye”.

It’s a pity that he has missed the lecture.

It occurred to me that he had left for Hong Kong.

It was said that he was translating the book into Chinese.

主语从句的引导词that一般不能省略，但从句放到后面的时候间或也省略that。如：It’s good you gave me such help.

It’s natural he should pass the exam.

在少数情况下，为了强调从句，或为了保持句中的平衡，可以不用形式主语it代替，而是直接把that从句放到主语的位置上，这时，不能省略that。如：

That he hasn’t finished the task is a fact.

That we need advanced equipment is obvious.

That she became a teacher may have been due to her mother’s influence.

That he is feeling better is the best news that we’re expecting.

That he didn’t attend the meeting made the manager angry.

用it作形式主语的that从句有以下四种不同的搭配：

1. it be + 形容词+ that-从句，如：

It is strange (surprising, possible, necessary, natural, obvious, true, important, good, unlikely, fortunate, quite clear, etc.) that...

2.it be + -ed分词+ that-从句，如：

It is said (believed, thought, arranged, decided, expected, known, reported, etc.) that...

3.it be + 名词+ that-从句，如：

It is a surprise (a pity, a shame, a fact, a wonder, a good thing, an honor, common knowledge, good news, etc.) that...

4. it be + 不及物动词+ that-从句，如：

It appears (happens, seems, came about, turned out, occurred to me, etc.) that...

19.2.2 由what, whatever, whoever引导的关系主语从句

由what引导的关系主语从句一般表示“...的事/东西”，what在从句中作了一定的成分（主语或宾语）。在结构上等于一个名词加一个定语从句，what = the thing which。也可以由whatever引导，表示“...的一切”，whatever = anything that ; 或由whoever引导，表示“一切...的人”，whoever = anyone who。如：

What he need is more practice.

What my parents said was right.

Whatever we talked about here must be kept secret.

Whatever he bought was useful.

Whoever wants to succeed must work hard.

Whoever didn’t attend the classes is wrong.

这一类的主语从句不能用形式主语it代替，只能放在主语的位置上。

19.2.3 连接代词和连接副词引起的wh-疑问主语从句

当主语从句是一个疑问句的时候，用疑问词（即连接代词或连接副词）引导主语从句，但从句的语序用陈述句的语序。如：

When we’ll have the sports meeting is still a question.

Whether we’ll go outing depends on the weather.

Where he is going to build a school hasn’t been decided.

What’s caused the fire is a mystery.

Who will host the activity isn’t known yet.

How he learns English hasn’t been talked about.

Why he put off the party remains unknown.

这一类的主语从句可以直接放到主语的位置上，也可以用形式主语it代替，把从句放到句子的后面，区别不大。如：

When he’ll come to our university hasn’t been made public.

→It hasn’t been made public when he’ll come to our university.

Whether she’ll come to my party won’t make much difference.

→It won’t make much difference whether she’ll come to my party.

但如果句子是疑问形式就只能用形式主语it代替，把从句放到句子后面。如：

Has it been announced when the train is to leave?

Has it made clear what we should do next?

Does it make any difference who buys the gift?

19.3 表语从句

表语从句是指一个从句作表语。表语从句一般由that, what, who, which, whether, when, where, why, how等连接词引导。

19.3.1 由that引导的表语从句

表语从句是一个陈述句陈述事实时，用that引导，that只是个引导词，在从句中不充当成分。如：

What’s troubling him is that he doesn’t have any experience in the work.

The fact is that we have fallen behind them.

His suggestion is that we should stay calm.

His parents’ wish is that he could become a doctor.

19.3.2 由whether引导的表语从句