We need clean air, but unfortunately, air pollution is generally present, especially in cities。

我们需要清新的空气，但遗憾的是，空气污染普遍存在，在城市中尤其如此。 [分析] 本句为了避免“尤其是在城市里”的表达不完整，增加了“如此”。

youdao

We need clean air, but unfortunately, air pollution is globally present, especially in cities.

我们需要清洁的空气，但不幸的是，空气污染是目前全球，尤其是在城市。

youdao

We need clean air, butunfortunately, air pollution is generally present, especially in cities.

我们需要清新的空气，但遗憾的是，空气污染普遍存在，在城市中尤其如此。

youdao

Just the same as the Forest Trees that clean the air and make Oxygen we breath and all living on earth need to Live.

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