b. 动名词和不定式作主语,一般都可以使用形式主语 it ,而将动
名词或不定式放在句尾。但是在下列句型中,一般宜用动名词,不
宜用不定式来代替:
It’s no use doing …
It’s no good doing…
It’s a waste of time doing …
例如:
It’s no use going there today; he won’t be at home.
It’s a waste of time arguing about it.
It’s no good waiting here. Let’s walk home.
而在 It’s important … / It’s necessary … / It’s advisable … / It’s
essential … / It’s fitting … 这类句型中,只能用不定式,如:
It’s important to learn foreign languages.
It’s quite necessary to read it many times.
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