As we have loitered, the clouds have gathered.

在我们闲逛的时候，云层集结起来。

youdao

Over the past three weeks, the storm clouds have gathered again over the government.

在过去三周里，不祥的阴云再次笼罩了政府。

《柯林斯英汉双解大词典》

THE rain clouds have gathered in liquid grey over the wetlands of the Sudd, the vast swamp that oozes either side of the White Nile as it curls through the heart of the new state of South Sudan.

白尼罗河蜿蜒穿过新成立的国家南苏丹，两岸广袤的苏德沼泽翻滚着泥浆。

youdao

Huge, angry storm clouds have gathered outside and the air is oppressively humid.

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