非谓语做主语时to do与doing该选哪个
1个回答

1)不定式作主语一般表示具体的某次动作.

To complete the 30 storied building in one year was quite a difficult task.

2)动名词作主语一般表示泛指意义的行为.(这时也可用动词不定式)

Seeing is believing.眼见为实.

注意:

1)当主语较长,谓语较短时,常用it做形式主语,而将不定式放到谓语的后面.

It is important for modern young people to master at least two foreign languages.

2)在It’s no use(或good, need)…或It’s useless(或worthwhile)…等结构中,常用动名词作真正的主语:It is no use sending him over.派他去没用.

3)在There is no +v.-ing…结构中,常用动名词作主语:

There is no joking about the matter.这事开不得玩笑.

4)比较状语从句里的主语用动词不定式还是用动名词,取决于主句里主语的形式:

It’s easier to read a foreign language than to speak it.

Reading a foreign language is easier than speaking it.阅读外语比讲外语容易.