have seen 和seen的差别是什么?（急!）
题目
have seen 和seen的差别是什么?（急!）
— He can't find his hat.Have you seen it?— Yes,of course.I _____ it on his bed just now.[ ] A.saw B.have seen C.had seen D.to see
答案
A.问题里是Have you seen,那你回复里也跟著用 have seen 就好了
如果对方问你 Did you see it?那你回答 I saw it on his bed 也可以
seen 是从 see > saw > seen 来的,
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