请教:2015大学英语三级(A级)全真模拟试卷3第2大题第6小题如何解答?
【题目描述】
The room is in a terrible mess; it ______ cleaned.A.mustn't have been
B.shouldn't have been
C.can't have been
D.wouldn't have been
【我提交的答案】: A |
【参考答案与解析】: 正确答案:C |
解析:对过去否定的推测用“can't have+过去分词”。
是不是有个说法,肯定用must,否定用can’t?