One might well ask how many European scientists it takes to turn on a light bulb.

有人可能会问经过了多少位欧洲科学家才点亮了灯泡。

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If this happens at night, yell for protection if you awaken, turn on a light, surround yourself in white light and demand they leave.

这可能会发生在晚上，如果你醒来，呼喊保护，打开一盏灯，让自己环绕着白色的光，要求他们离开。

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So if dusk's approaching and you can't put that book down, there's no need for alarm. But you'll be a lot more comfortable if you turn on a light.

因此，当黄昏来临时，如果你还不想把正在看的书放下，请不要惊慌，这并不会直接影响您的视力，如果想让眼睛觉得更舒服些，只要把一盏灯点亮就好。

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We'll turn the light back on for a second here.

我们马上要开灯。

麻省理工公开课 - 化学原理课程节选

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

When I turn on a light switch, I can imagine the chain reaction.

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Once the Zeo headband captures that unique eye signal, and transmits it via sleepstreamonline.com to the second dreamer, it will turn on a colored light where the other dreamer is, to send them a cue too .

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Even when confining their predictions to the next few decades, the Killer Bs painted the future with broad brushstrokes that were heavy on the cultural impact of technology and light on how to turn a profit on the stuff.

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