Dad is sleeping. Please a little.A. turn onB. turn offC. turn upD. turn down

问题补充：

Dad is sleeping. Please a little.

A. turn on

B. turn off

C. turn up

D. turn down

答案：

A. turn on

B. turn off

C. turn up

(答案→)D. turn down

解析：turn on打开，发动；turn off关掉，关闭；turn up 出现，发生；turn down减小，关小。句意：爸爸睡觉了。请把音量关小一点。结合语境可知选D。