Lucy: Perhaps because of the dirty air.

露西：可能是空气污浊的原因。

youdao

Moreover, the topography there resembles that of metropolitan Phoenix – a valley surrounded by mountains that trap the dirty air within.

而且这里的地形类似菲尼克斯，也是群山环绕的峡谷地形，使肮脏的空气汇聚于此。

youdao

Among other weaknesses, the measures cities must employ when left to tackle dirty air on their own are politically contentious, and therefore vulnerable.

除其他弱点外，城市在独自应对空气污染时而必须采取的措施存在政治上的争议，因此也很易受到攻击。

youdao

As an early environmental activist, I worried about my baby breathing the dirty air in New York City.

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Sure, environmentalists will insist that more drilling in the U.S. will just continue our addiction to fossil fuels and will dirty up the air and water.

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The afternoon pollution had set in and the air was a dirty shade of brown.

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