Stay awake！You should know that it to sleep in class.
A. doesn’t permit
B. is not permitted
C. will not be permitted
D. was not permitted
网友回答
A. doesn’t permit
(答案→)B. is not permitted
C. will not be permitted
D. was not permitted
解析：考查时态及语态，保持清醒！你应该知道课上不允许睡觉。根据语境应用一般现在时态，且表示被动，所以选C。