问题
选择题
--- Perhaps John’s not in. --- _______. Look, the light is on.
A．Yes, he can be at home.
B．No, he couldn’t go out
C．Yes, he must be at home
D．No, he needn’t go out
答案
答案：C
考查情态动词表推测。Yes, he is.“不，他在家。”；must表示肯定推测，意为“一定”。故选C。