Mary ___on her new priject late last night ,so she felt sleeply in the office this morninga.must work b.must have been working c.must be working d.must have been worked选什么.
问题描述：
Mary ___on her new priject late last night ,so she felt sleeply in the office this morning
a.must work b.must have been working c.must be working d.must have been worked
选什么.
答
如果是过去完成时应该是have done 吧
答
接受大家的意见 表示失误 D是被动 选B
答
嗯,是选B,因为昨晚的事儿,属于过去式,这句话意思是,他一定做完工作的很晚,所以今天早上困.也就是说对过去进行推测,而对过去的推测固定用法就是,must have done,所以不是B,就是D,但是D表示被动,不能翻译成被工作,明白了么.
答
选择b，表示昨天晚上她一直在工作，这里选择完成进行时，表示昨晚一直持续工作