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。