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, 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。

youdao

"And we need to clean up so that they can come and build new residential places for our families here."

VOA: standard.2009.10.04

"It was so expensive to clean up after this crisis, we need more safety - even if it makes loans a little more expensive."

VOA: standard.2010.03.16

We need clean water not only to sustain ourselves, but also for other basic necessities such as farming and sanitation.

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We need clean coal in the U.S., and melding the technology with oil recovery is a smart way to make it economic.

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We need clean capacity.

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