We were having a meeting suddenly someone knocked at the door.A. becauseB. whenC. asD. wh

发布时间：2020-08-16 19:56:40

We were having a meeting      suddenly someone knocked at the door.
A. because
B. when
C. as
D. while

网友回答

A. because
(答案→)B. when
C. as
D. while
解析：考查固定结构。Be doing sth. when…正在做某事，这时……；when在这是并列连词。选B。
以上问题属网友观点，不代表本站立场，仅供参考！