It is frustrating now because we are stagnating at a terrible air quality level.

现在的情况很令人沮丧，因为我们停滞在一个很糟糕的空气质量中。

youdao

Urban air quality level is token by air quality index (API), whose spatiotemporal change can reflect the change of urban air quality.

城市空气质量水平是以空气质量指数(API)来表征的，API的时空变化可以反映城市空气质量的变化过程。

youdao

According to the air quality level of WHO issuance, at least 80% city dwellers are living in the unacceptable air condition, which threatens their health.

按WHO指导值来衡量，城市居民至少有80%的人是在不可接受的空气质量下生活，对人体健康构成极大威胁。

youdao

If you were outdoors in air quality of that level, you'd be told to go indoors and not do any physical activity.

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