Class Two ____ taking their lessons when there was a knock at the_英语解答

Class Two ____ taking their lessons when there was a knock at the door.为什么
A. is B. areC. wasD. were

人气：486 ℃　时间：2019-10-11 04:27:18

解答

B.are 这里表示同学在上课
是指人所以用复数形式