单选题
Mrs. Brown is supposed ______ for Italy last week. A. to have left B. to be leaving C. to leave D. to have been left
【正确答案】
A
【答案解析】[解析] be supposed to have done sth. 作“本应该做某事”讲,相当于should have done, 可以算是一种特殊的虚拟语气,表示过去本应该做而实际未做的事情,例如:The problem of storing the sun's heat is supposed to have been studied by scientists all over the world. 大家都认为贮存太阳热能的问题已为全世界的科学家研究过了。You are supposed to have been here one hour ago. 你们一个小时前就该在这里。