The hills merged into the dark sky behind them.

山峦渐渐隐入背后漆黑的夜空之中。

《牛津词典》

In most cities the sky looks as though it has been emptied of stars, leaving behind a vacant haze that mirrors our fear of the dark.

在大多数城市里，天上看起来好像没有星星，仅剩一层薄薄的雾霾，这反映出我们对黑暗的恐惧。

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It's like a mirage, where heat causes the bending of light rays and cloaks the road ahead behind an image of the sky.

实验就象海市蜃楼，在高温下，光线发生弯曲，从而前面的道路就看不见了，而只能看到后面的天空图像。

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Never have the muscled bodies looked so lifelike, the sky behind the "Last Judgment" so luminous.

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This has helped earn Mr. Fyfe the position as inaugural chairman of Star Alliance, the world's largest airline alliance, not to mention requests from other airlines for the technology behind the "sky couch, " which offers flat-bed seating in economy.

WSJ: Managing in Asia: A Focus on People Keeps Little Guy Flying High

The giant order of those arches rising two stories high creates an effect of prim grandeur that allows the whole, seen alone against the sky behind, to command the common before it.

WSJ: Prim Grandeur, Elegant Geometries | Charles Bulfinch | Lancaster Meetinghouse | By John Wilmerding