单选题 Sharon is supposed to be here at nine o"clock. She ______ about our meeting.

A、 would have forgotten
B、 should have forgotten
C、 ought to have forgotten
D、 must have forgotten

【正确答案】 D

【答案解析】[解析] 句意：Sharon本应该9点就在这里了，她一定是忘记我们的会议了。“must have done”结构的意思是：肯定做过某事，表示对已发生事情的肯定推测，“would have done”结构通常表示虚拟语气，“should/ought to have done”结构表示本来应该做某事，而实际没有做。D选项符合句意。