Wind is a current of air caused by a vacuum caused by hot air rising.

风是由热空气上升产生真空而引起的空气流动。

《柯林斯英汉双解大词典》

She looked at him with a defiant air.

她用蔑视的神情望着他。

《牛津词典》

A major air-sea rescue is under way.

一项重要的海空营救行动正在进行中。

《柯林斯英汉双解大词典》

The Department of Agriculture, for example, provides biologists to help study wildlife that could be a danger to air travel.

VOA: special.2009.04.01

Then he flung outward, feet first, with a swish, Kicking his way down through the air to the ground.

然后，纵身一跳，他两脚先伸出去，在空中乱踢乱舞，于是飕的一声，降落到地面。

耶鲁公开课 - 现代诗歌课程节选

dT/dp is mu JT. So for a real gas like air, this is a positive number. It's not zero.

所以对于像空气这样的真实气体，这是一个正数，不等于零。

麻省理工公开课 - 热力学与动力学课程节选

Earlier this month, a Air France plane clipped a Delta Connection flight on a runway at New York's John F.

CNN: Plane clipped by tractor-trailer at Boston airport

How do we make a air control system that reduces delays?

WHITEHOUSE: Backyard Discussion on Women and the Economy

Dug in 1940 as London was blitzed by German bombers, the tunnels were designed as a air-raid shelter for up to 8, 000 people, and as a possible last-ditch base for the government in the event of an invasion.

ECONOMIST: Snooker, piranhas and a hotline to Moscow