英语语法

第10讲 名词性从句

【定义】一个句子在另一个句子中充当主语、宾语、表语、同位语，相当于名词，故称为名词性从句。

【四大从句】名词性从句分为主语从句、宾语从句、表语从句和同位语从句。

一、主语从句

一个句子在另一个句子中充当主语，即句子充当主语，该句子称为主语从句。

【完成例句】

根据句意选词填空(that, if, whether, why, when, what)

(1) That he will succeed is certain.

(2) Whether he will go there is not known.

(3) What he said is not true.

(4) When the meeting will be held has not been decided yet.

【结论】 ①that－从句，从句为一个句意完整的陈述句，没有具体意义，不充当句子成分，只起标志性作用，但that 不能省略。

②whether －从句，从句来源于一般疑问句，whether不能省略，意为“是否”，不能用if替换。

③特殊疑问词－从句，从句来源于特殊疑问句，特殊疑问词不能省略，意思为特殊疑问词本来的意思，在从句中充当句子成分。

【疑难1】Who he is is none of my business.

【疑难剖析1】任何从句要用陈述句语序，即主谓语序。

【疑难2】That he likes English is known to us all.

What he said at the meeting made me sad.

【疑难剖析2】主句时态为过去时，从句时态为过去的某一时态；主句时态为现在时或将来时，从句时态视具体情况而定。

【疑难3】That 2010 Asian Games are successful is known to all.

【疑难剖析3】单个句子作主语，视为单数。

【疑难3】It is a pity that you didn't go to see the film.

It doesn't interest me whether you succeed or not.