When I home, I caught a thief stealing from a passerby.
A. headed
B. was heading
C. has headed
D. had headed
网友回答
A. headed
(答案→)B. was heading
C. has headed
D. had headed
解析：B 考察动词时态。句义：正当我往家走的时候，我发现一个小偷在偷路人的东西。根据句义可知本句叙述的是在过去某个时间正在发生的动作，所以使用过去进行时。故B正确。