At the beginning of class, the noise of desks _____ could be heard outside the classroom. A．opened a

题目简介

At the beginning of class, the noise of desks _____ could be heard outside the classroom.

A．opened and closed	B．to be opened and closed
C．being opened and closed	D．to open and close

题型：单选题难度：偏易来源：不详

此处表示被动和进行，故答案为C，现在分词的被动语态做定语。