The clutch is also used to disengage the engine from the drive train whenever the gears in the transmission are being shifted from gear ratio to another.

此外，在改变变速器齿轮的传送比时(换档时)，离合器也被用于切断传动系与发动机之间的连接。

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If you drive too slowly in third gear, you'll lug the engine.

如果你在第三档时驶得太慢，你将不能很快带动引擎。

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One possible use of this technology is to provide context information from the car, something like the engine speed has reached 2000 rpm, the parking brake has been disengaged, the transmission gear is in drive and the brake pedal is fully off the floor.

FORBES: Automotive/Tech Companies Trying to Bring the Web to the Car