About the time the three climbers were halfway down, clouds blotted out the sun.

当3位登山者下到半山腰的时候，云层遮住了太阳。

《柯林斯英汉双解大词典》

If the birds have not flown for three years, they will soar into the clouds. If they have not sung for three years, their songs will take everyone by surprise.

三年不蜚，蜚将冲天；三年不鸣，鸣将惊人。

《新英汉大辞典》

For a few hours it took the capital back to the chaos and fear that reigned three or more years ago. Clouds of black smoke hung over the airless city.

首都巴格达在几小时内又回到了三年多前混乱和惊恐的局面，黑色的烟云长久地笼罩在城市的上空。

youdao

So which of these three clouds on the horizon worries me the most?

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But there are three black clouds over this sunny scene.

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Visibility was three miles, but the clouds were at 400 feet.

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