当气温开始降低，冰从高层云中落下来的时候，它们会开始形成平整的六边形的晶体。

When the atmosphere is cold, ice sometimes forms flat six-sided crystals as it falls from high-level clouds.

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当气温开始降低，冰从高层云中落下来的时候，它们会开始形成平整的六边形的晶体。

When the atmosphere is cold, ice sometimes forms flat six-sided crystals as it falls from high-level clouds.

youdao