單項選擇—Thereissomebodyatthedoor.Who
來源：國語幫 1.66W
問題詳情：
單項選擇
—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
知識點：情態動詞
題型：選擇題
