Atmospheric pressure then pushes the piston back down the cylinder, and if anything (such as a pump) is attached to the piston, some useful work can be done.

于是，气压就会再次将活塞推至汽缸底部。而假如有诸如水泵这样的物体与活塞连接，就可以在活塞的带动下完成一些工作。

youdao

Plug-in hybrids, meanwhile, could charge at night, when demand is low, and even pump power back to the grid while parked during the day.

同时，当夜晚用电低谷时，可以利用混合动力装置充电(译注：wikipedia)，甚至可以在白天再把电力传输回电网里。

youdao

I back my car up to the next pump, hurry to get away from her.

为了躲她远点，我匆匆调转车头向下一个油泵驶去。

youdao

So the city, in 1867, sank an immense cylinder, or crib, 2 miles from shore to pump fresh water back to the inhabitants.

FORBES: A most unromantic river

Smit, which in charge of salvaging Prestige before it sank, said the operation - to pump the oil back to the surface - would cost nearly 50m euros and take several months to complete.

BBC: French sub to try patching Prestige

This is what this data is supposed to monitor, but the well flow evidence would appear to have been ignored, because at this point the BP rig supervisors should have gone to a well kill operation and started to pump heavy mud back into the well bore to restore the primary control mechanism.

WSJ: The Oil Disaster Is About Human, Not System, Failure