Dependence on long-distance trade also meant that the great empires of the Middle East were built both literally and figuratively on shifting sand.

对长途贸易的依赖也意味着，伟大的中东帝国无论是实际上还是象征意义上，都是建立在流沙之上的。

youdao

Some measures are needed to secure the farmland against shifting sand.

需要采取措施使农田免遭流沙的侵袭。

youdao

Shifting sand of the ocean floor helps the sculptures evolve over time.

久而久之海底的流沙有助于雕塑的形成。

youdao

The managers, as was true of the majority report and the independent counsel referral (ph) before that build their theory in this case not only any pillars of obstruction, but on shifting sand castles of speculation.

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Houses built on shifting sand, very badly.

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Stony ridges gave way to tumbled boulders, slopes of sifted gravel, and then sand, blown into shifting dunes.

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