Students shall turn off light and lock windows and doors before they leave classrooms.

离开教室时应随手关灯，关好窗户和锁好门。

youdao

Turn off the light!

把那灯关了！

youdao

You don't need a light switch or a light bulb or an iPhone app to turn something on or off.

你不需要电灯开关、灯泡或苹果手机应用程序来打开或关闭某些东西。

youdao

They used light-sensitive molecules to turn on and off nerve cells in the deep brain structure of mice.

VOA: special.2009.04.07

You don't need a light switch or a light bulb or an iPhone app to turn something on or off.

你不需要一个电灯开关,或者一个电管,或者打开关闭一个iPhone应用程序。

哈佛公开课 - 计算机科学课程节选

He could turn off a light and then jump into his bed before the room got dark.

VOA: special.2009.01.24

If so, how much sleep do you get, and when do you turn off the light?

FORBES: Give Yourself A Bedtime

However, if the solution is a simple DIY remedy like tightening your gas cap, you can go ahead and turn off the light with the app itself, saving you time and money.

ENGADGET: Automatic Link connects phone and car for better driving, we go hands-on (video)

Will the last one out please remember to turn off the black light?

FORBES: From Dungeon to Corner Office: Evolution of the CIO