Usages of yánzhòng
现在 很多 城市 的 空气 污染 很 严重。xiànzài hěnduō chéngshì de kōngqì wūrǎn hěn yánzhòng.
Nowadays, air pollution in many cities is very serious.
空气 污染 这么 严重， 一 个 原因 是 塑料 垃圾 太 多。kōngqì wūrǎn zhème yánzhòng, yì gè yuányīn shì sùliào lājī tài duō.
For air pollution to be this serious, one reason is that there is too much plastic trash.
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