–Sometimeisknockingatthedoor.Who

问题详情：

–Sometime is knocking at the door. Who ______ it be?

        --It ______ be Tom. He is still in the school.

         A. can; can’t      B. can; mustn’t     C. might; could    D. might; may

【回答】

A

知识点：情态动词

题型：选择题