Air hasn't much weight.

空气没有多少重量。

youdao

Air not only occupies space but it also has weight.

空气不仅占据空间，而且它还具有重量。

《新英汉大辞典》

Water has weight, and air also has weight.

水有重量，空气也有重量。

youdao

Atmospheric pressure is caused by the weight of the air over our heads.

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But that evening his body was compressing: the weight of the air was on him, flattening his libido and his trust in humankind.

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These are the impediments to the movement of people and goods brought on by Sept. 11: the wasted hours of employees showing IDs to get into their building, the delays at the airport, the backlog of trucks at the border, the increased cost of air freight, the dead weight of higher insurance premiums.

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