But what about pollution sources that have already been built?
但是，那些已经建成的污染源又该怎么办？
It is extremely urgent to control the pollution sources.
指出对污染源的治理已迫在眉睫。
Gold mine tailing is one of an important pollution sources.
黄金矿山尾矿是重要的污染源之一。
It is a kind of pollution sources, and a kind of potential resource.
它既是一种污染源，又是一种潜在的资源。
Road traffic noise has become one of the major urban pollution sources.
交通噪声已成为城市主要污染源之一。
Water pollution sources are: construction encampments, bridge construction.
水污染源有：施工营地、桥梁施工。
The arterial road in city has become one of the important city pollution sources.
城市干道已成为城市主要污染源之一。
Recently, cooking fume is one of the most important air pollution sources in many cities.
近年来，饮食业油烟污染已成为城市大气污染的主要来源之一。
Recently, cooking fume is one of the most important air pollution sources in many cities.
近年来，饮食业油烟污染已成为城市大气污染的主要来源之一。
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