作业帮过去完成时能否与表示过去的时间状语从句连用?我看到说,例如:He must have finished homework yesterday,didn't he?说此时的反意疑问句的助动词与从句谓语一致,那么谓语助动词是had 还是did?
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过去完成时能否与表示过去的时间状语从句连用?我看到说,例如:He must have finished homework yesterday,didn't he?说此时的反意疑问句的助动词与从句谓语一致,那么谓语助动词是had 还是did?
过去完成时能否与表示过去的时间状语从句连用?
我看到说,例如:He must have finished homework yesterday,didn't he?说此时的反意疑问句的助动词与从句谓语一致,那么谓语助动词是had 还是did?
过去完成时能否与表示过去的时间状语从句连用?我看到说,例如:He must have finished homework yesterday,didn't he?说此时的反意疑问句的助动词与从句谓语一致,那么谓语助动词是had 还是did?
反问句中,若陈述句谓语部分有“must have done”,而且有表示过去的时间状语,问句部分用didn't；若没有表示过去的时间状语,问句部分用haven't或hasn't.二者的区别在于,指明时间的反问句,有强调在该时点（并非说话当时）的状态的意味,所以用过去时表示对当时状态的疑问~或者可以换一种方式理解,问话人可能还有一层意思,就是“他是否是昨天下午完成的作业”,也就是说动作发生在昨天下午.特别是考虑到表达后一种意思的要求,才有了上述区别,否则的话,该意思就无法区别于“是否已经完成”的意思而明确的表达了~
一、对现在情况的推测,问句部分用主动词（do,be)一般现在时的适当形式.若是现在进行时,问句部分用现在进行时的适当形式表示.若是there be结构,问句用isn't/aren't there.如：
1)He must be there,isn't he?
2)He must have a big family,doesn't he?
3)He must be waiting outside,isn't he?
4)There must be some students in the room,aren't there?
二、对已发生的过去情况的推测,若陈述句谓语部分有“must have done”,而且有表示过去的时间状语,问句部分用didn't；若没有表示过去的时间状语,问句部分用haven't或hasn't.如：
1)They must have gone there last night,didn't they?
2)They must have arrived by now,haven't they?（根据by now来判断）
3)They must have been to the Great Wall,haven't they?
三、若是被动,应按被动结构来处理.如：
1)The room must have been cleaned yesterday,wasn't it?
2)The room must have been cleaned,hasn't it?
四、若句中有表示过去完成时的时间状语,问句部分应用hadn't.如:
They must have learnt 5000 English words by the end of last term,hadn't they?
(本题中must表推测,如果将它去掉,还原为真实句就是They had learnt 5000 English words by the end of last term.因此,反意问句是hadn't）