Question

____ for a bus, I was reading a magazine.

A．While was waiting

B．While I waiting

C．While I am waiting

D．While waiting

Answer 1

D

有些时间状语从句中的谓语动词如果有动词be，主语又与主句的主语一致，或主语是it是，则从句的主语和谓语的一部分（特别是动词be）常常可以省略。