Question

【题目】Yesterday, I the subway home when I suddenly found I was on the wrong line.

A. took B. was taking C. had taken

Answer 1

【答案】B

【解析】句意：昨天，当我突然发现我拨错电话的时候，我正在乘地铁回家。这里是when引导的时间状语从句，当某个动词发生的时候，某个动作正在进行，根据题意，故选B。