一句要表达的汉语是:对于情态动词 Can,could,may,大家必须要确定什么时间用哪一个。
我看一句英文是: For can,could and may, let's be really sure when to use which one.
英文里的to use是不定式吗?如是不定式,那是不是用在了谓语的地方上,是不是就不对?如错误,正确英文应怎么样表达?
疑问词+to do不定式,其实是名词性疑问分句的一种简略。when to use which one = when we should use which one. 即句子省略了主语+情态动词,把情态动词后的不定式改为带to的不定式。又如:
I don't know what to say.
= I don't know what I can/should say.
He didn't say when to come.
= He didn't say when he would come.