在二冲程发动机中你必须混和燃料和气体，因为气缸壁上的孔阻止使用活塞环密封燃烧室。

You have to mix oil into the gas in a two-stroke engine because the holes in the cylinder wall prevent the use of rings to seal the combustion chamber.

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这是因为通过练习，你的嘴唇会紧紧地密封住吹孔，这样气流就不会在嘴唇边漏掉了。

This is because, with practice, your lips form a better seal around the holes, so that air does not escape.

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打开密封的地下水疏水管道人孔以试图定位进入系统的氚源。

Opening sealed subsurface drain line manways to attempt to localize the source of tritium into the system.

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