At the beginning of class, the noise of
题型:选择题
问题:
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
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