They must have been to the USA,have not they?与He must have been t_英语解答

They must have been to the USA,have not they?与He must have been to the USA,was not he?区别
最好讲讲为什么句子主语一换,must反义疑问句就不一样了?

人气：216 ℃　时间：2019-12-12 02:19:14

解答

你好,你没有搞懂这些句子的用法:在这两个句子中,因为都没有时间状语的修饰,所以句子发生的时间不确定,答案也不确定,请你看以下的句子,They must have been to the USA,haven't they?He must have been to the USA,ha...