Have you ever seen kids smile as they stare at thin air, and wonder what made them giggle?

你有没有过看到孩子们对着空气笑，并好奇是什么让他们咯咯笑呢？

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The air was thin and crisp, filled with hazy sunshine and frost.

空气稀薄而清新，弥漫着朦胧的阳光与霜霭。

《柯林斯英汉双解大词典》

Thirteen years ago she found herself having to conjure a career from thin air.

十三年前她认识到自己得白手起家闯出一番事业来。

《柯林斯英汉双解大词典》

It includes long,thin,red and white rocks that reach high into the air like fingers on a hand.

VOA: special.2009.04.15

Things are not "made up" in Frost, "not made up" in the sense of imagined, called up out of thin air, like fairies and elves.

弗罗斯特的诗歌里没有编造，没有想象，像仙女和精灵那样的凭空想象。

耶鲁公开课 - 现代诗歌课程节选

Drop several seeds over the surface of the pot and cover with a thin layer of vermiculite, a substance that can hold air, water and nutrients.

VOA: special.2009.04.21

Flying high in the earth's atmosphere, where the air is thin, is, he says, rather like flying near the surface of Mars.

ECONOMIST: Planetary pretenders

In the thin air, the kids promptly fell asleep and Marji fumbled with her movie camera.

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Building a company out of thin air is one of the hardest human pursuits.

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