问题补充：
A boy with two dogs when the earthquake rocked the city.
A. were sleeping
B. is asleep
C. was sleeping
D. are asleep
答案：
A. were sleeping
B. is asleep
(答案→)C. was sleeping
D. are asleep
解析：句意：当这个城市发生地震时，一个男孩和两条狗正在睡觉。句中有when所引导的过去的时间状语，句子用过去进行时，故选C
