Plastic straws are by no means the biggest source of plastic pollution, but they've recently come under fire because most people don't need them to drink with and, because of their small size and weight, they cannot be recycled.

塑料吸管绝对不是塑料污染的最大来源，但是它们最近饱受抨击，因为大多数人不需要用它们来喝饮品，也因为它们尺寸小、重量轻，无法回收利用。

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As well as the noise, traffic, loss of arable land and threat to birds, airports are a major source of pollution and greenhouse gas emissions.

机场不仅导致了噪声、交通堵塞、耕地流失，威胁鸟类，还是主要的污染源和温室气体排放源。

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"Residents near the lake have showed support for the closure of chemical companies, the major source of pollution, because this concerns the livelihood of our offspring," he said.

他说湖边的居民已经表示出对湖边最主要的污染源—化学工厂的关闭，因为这直接关注湖里生物的繁衍。

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