They are controlled by molecular triggers that switch on and off on demand.

它们由能够根据需要开启或关闭的触发分子控制。

youdao

“There’s always the switch on, switch off button on the phone. So it’s your choice”, he says.

“因为手机上总有一个开机关机的按扭，这完全是个人的选择”他说道。

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Although the rats had regained the ability to walk, they were still reliant on an electrical wire to switch their movements on and off.

虽然这些老鼠已恢复了行走能力，但是，它们仍需依靠一根电线来带动自己行走及停止。

youdao

So now it's not just that the on-off switch is stuck in off, the brain's no longer capable of engaging in these higher order P-functions.

所以现在看来就不是开关被卡住，大脑已经不再有能力,实行这些高级的人格功能。

耶鲁公开课 - 死亡课程节选

Of course, to turn the on-off switch on is harder when somebody's in a coma.

当然要开启这个开关难度更大,当人陷入昏迷。

耶鲁公开课 - 死亡课程节选

The cognitive structures are still there, but the on-off switch is switched to off.

认知结构仍然存在，只是开关还没有被开启。

耶鲁公开课 - 死亡课程节选

With a mechanical keyboard, on the other hand, each key press triggers an actual on-off switch a feeling as solid as flicking on the lights.

WSJ: Keys That Really Click

The earpiece has an on-off switch, a three-stage volume control and uses a rechargeable battery.

WSJ: Testing, Testing...Can You Hear Better Now?

They seem only to care about where the on-off switch is located.

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