—Tom must be at home because the light in his house is on. —He       be at home,

题型：不详难度：来源：

—Tom must be at home because the light in his house is on.
—He       be at home, because I saw him playing basketball on the playground.
A. must B. can’t   C. mustn’t

答案

B

解析

试题分析：句意:-Tom一定在家里因为他家里的灯亮着。-他不可能在家，意为我看见他在操场打篮球了。根据这个情景可知，这里两个人是在进行推测，根据第二个人的话可知，他很确定Tom不在家里，表示否定的推测应该用can’t,意思是不可能。must 表示推测时只能放在肯定句中。故选B。