Mary ___on her new priject late last night ,so she felt sleeply i_英语解答

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.

人气：339 ℃　时间：2020-05-07 16:02:45

解答

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.