但是,在进气和排气行程中,一些可燃混合气不可避免地进入排气系统,并且总会有一些燃烧物滞留在气缸中,致使燃料不能充分燃烧。

• "But it is wasteful of gasoline, as some mixture inevitably finds its way into the exhaust system on the combines intake/exhaust stroke, and there are always some combustion products left in the cylinder which reduce the rapid Burning of the fuel."