把公路污染源界定为移动污染源、固定污染源，临时污染源和伴生污染源；

The road pollutant sources are demarcated as moving, fixed, temporary and associate sources.

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空气污染通常是与主要的固定污染源，但排放的最大来源是移动来源主要是汽车。

Air pollution is often identified with major stationary sources, but the greatest source of emissions is mobile sources, mainly automobiles.

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