Before you leave the classroom, please the lights.
A. turn up
B. turn down
C. turn on
D. turn off
网友回答
A. turn up
B. turn down
C. turn on
(答案→)D. turn off
解析：此题重点考查四个短语的区别，turn up出现，开大；turn down 减小，关掉；turn on 打开； turn off关掉。句意：在你离开房间之前，请把灯关掉。结合语境可知选D。