The students listen to the teacher carefully in class.(改为被动语态)

问题描述:

The students listen to the teacher carefully in class.(改为被动语态)
The teacher( )( )( )carefully by students in class.
每空一词.
是不是填was listen 又好像怪怪的.

是is listened to
本句是一般现在时的,该被动时态不变的