Flags and bunting hung limply in the still, warm air.

旗子和飘带在静止、温暖的空中无力地垂着。

《柯林斯英汉双解大词典》

Gravity pulls down cold air, and warm air rises.

重力令冷空气下沉，暖空气上升。

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With the arrival of warm and pleasant weather, flowers are blooming in the warm air.

随着温暖宜人天气的到来，鲜花在温暖的空气中盛开。

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Cold weather moves south and combines with the last of the warm air from summer.

VOA: special.2009.06.09

I'm hot, compared to the air of the room, or cold if I'm somewhere that's warm.

我相对于室内的空气是热的，或是冷的如果我呆在一个温暖的地方。

麻省理工公开课 - 热力学与动力学课程节选

During spring, warm air moves north and mixes with cold air remaining from winter.

VOA: special.2009.06.09

In the winter, warm air near the ceiling is pushed downward, reducing heating bills.

FORBES: How Big Ass Fans Can Improve Life for Working People, Fix the Economy, and Help Solve World Health Problems.

Warm air at ground level enters via tangential inlets around the base of the wall.

ECONOMIST: Harnessing artificial tornadoes as an energy source

The action of warm air rising rapidly through the atmosphere is usually a trigger for sustained, sometimes violent, rainfall.

BBC: Turbulence ahead: Flight heads into storm's heart