气阀机构就相当于一个交警，指挥空气和燃料在合适的时间进出引擎。

It lets air and fuel in and out of the engine at the proper time.

youdao

气阀机构就相当于一个交警，指挥空气和燃料在合适的时间进出引擎。

It lets air and fuel in and out of the engine at the proper time.

youdao