Today is Wednesday. He be at home. He be at school.A. cant; canB. cant; mustC. mustnt;

问题补充：

Today is Wednesday. He be at home. He be at school.

A. can ; can

B. can ; must

C. mustn ; must

D. mustn ; can

答案：

A. can ; can

(答案→)B. can ; must

C. mustn ; must

D. mustn ; can

解析：句意：今天是星期三。他不可能在家。他一定在学校。在肯定句中表示推测可以用must，在否定句中表示推测可以用can’t。