The Reads_________(not listen) to the radio at that time.为何用were not listening

题目

The Reads_________(not listen) to the radio at that time.为何用were not listening
为什么不能是过去式 didn't listen?

答案

【答案】：were not listening
过去进行时表示过去某一段时间或某一时刻正在进行的动作.at that time“在那时”,正是过去进行时的时间标志.本句的意思是“雷德一家那时正在听收音机.”