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。

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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.

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That, in turn, would warm the air around them and warm air, as every schoolchild knows, rises.

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

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