单项选择—Thereissomebodyatthedoor.Who
来源：语文精选馆 1.76W
问题详情：
单项选择
—There is somebody at the door. Who ______ it be? Is it the postman?
—No. It _______ be him. It’s just 7:00 o’clock. It’s too early.
A. may, mustn’t B. may, can’t C. must, needn’t D. can, may not
【回答】
B
知识点：情态动词
题型：选择题
