He must have done his homework last night,didn't he? 这里为什么用didn't而不用haven't?错了 是 hasn't
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He must have done his homework last night,didn't he? 这里为什么用didn't而不用haven't?错了 是 hasn't
He must have done his homework last night,didn't he? 这里为什么用didn't而不用haven't?
错了 是 hasn't
He must have done his homework last night,didn't he? 这里为什么用didn't而不用haven't?错了 是 hasn't
must have done 的结构,前句强调对过去情况的猜测时(一般有过去时间状语)
附加部分用 didn’t + 主语.如果前句强调动作的完成,附加部分则用 haven’t (hasn’t ) + 主语.
He must have met her yesterday,didn’t he
You must have been to Beijing,haven’tyou
因为句中有一个明显的时间短语last night, 在这种情况下,反义疑问句就用过去时。如果没有last night, 就用现在完成时。额? 那不是矛盾了吗。 last night 是过去世的标志,而这里面却出现了 完成时的句子结构..........must have done 恰恰是对已经发生的事情的推测。如: 1. He must have sold the house. 他一定是把房子...
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因为句中有一个明显的时间短语last night, 在这种情况下,反义疑问句就用过去时。如果没有last night, 就用现在完成时。
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