Question

【题目】By the time I walked into class, the teacher ________ the lesson already.

A. had started B. starts C. start D. was started

Answer 1

【答案】A

【解析】

句意：当我走进教室时，老师已经开始上课了。A. had started过去完成时；B. starts动词三单式，一般现在时；C. start动词原形，一般现在时；D. was started一般过去时态的被动语态。start这一动词发生在走进教室之前，walked是walk的过去式，表示“动作过去的过去”要用过去完成时，故答案选A。