Don’t forget the lights when you leave the classroom.A. turning offB. turning onC. to tur

问题补充：

Don’t forget the lights when you leave the classroom.

A. turning off

B. turning on

C. to turn off

D. turn off

答案：

A. turning off

B. turning on

(答案→)C. to turn off

D. turn off

解析：本题的含义为当你离开房间的时候不要忘记关掉灯，forget to do表示忘记未做的事情，turn off表示关上的含义，故本题选C。