The room is in a terrible mess,it ___ cleane;a、can’t have been b、_英语解答

The room is in a terrible mess,it ___ cleane;
a、can’t have been
b、shouldn’t have been
c、mustn’t have been
d、wouldn’t have been

人气：451 ℃　时间：2020-02-02 10:24:56

解答

这个应该是虚拟语气吧,不可能已经干净了,应该是D,过去式表虚拟