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Mary ______ my letter; otherwise she would have replied before now.A.has receivedB.ought to have receivedC.couldn’t have receivedD.shouldn’t have received为什么不是D
题目详情
Mary ______ my letter; otherwise she would have replied before now.
A.has received
B.ought to have received
C.couldn’t have received
D.shouldn’t have received
为什么不是D
A.has received
B.ought to have received
C.couldn’t have received
D.shouldn’t have received
为什么不是D
▼优质解答
答案和解析
这题选C
couldn't have done 意为“很可能还没做”,客观性强,相对于must have done (很可能做了)来说.
句子意思:玛丽可能还没有收到了我的信;否则她在此之前就回复了.【“她没有回复”是一个客观依据,虽然不能充分证明“她没有收到我的信”】
shouldn't have done 意为“应该还没做“,表达主观性强
She shouldn't have left work yet.I'll call her office.(她应该还没下班.我打她办公室电话看看.)
couldn't have done 意为“很可能还没做”,客观性强,相对于must have done (很可能做了)来说.
句子意思:玛丽可能还没有收到了我的信;否则她在此之前就回复了.【“她没有回复”是一个客观依据,虽然不能充分证明“她没有收到我的信”】
shouldn't have done 意为“应该还没做“,表达主观性强
She shouldn't have left work yet.I'll call her office.(她应该还没下班.我打她办公室电话看看.)
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