Ennis, weather-eyed, looked west for the heated cumulus that might come up on such a day but the boneless blue was so deep, said Jack, that he might drown looking up.

埃尼斯用他那饱经风霜的眼睛向西了望，但见一团浓云将至未至。头上的青天依然湛蓝深邃，就像杰克说的，他都要淹死在这一片蔚蓝之中了。

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Cumulus clouds are big, white masses of fair-weather clouds that drift across the daytime sky. But heavy layers of cumulus clouds can threaten rain. (4)

积云是白色的、标志着好天气的大云团，在白日的天空中飘浮。但是，厚厚的积云层可能是要下雨的征兆。

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He introduces the half-dozen main types of clouds as if they were his oldest friends: there is the towering, thunderous cumulonimbus, the beautiful cirrus, the fluffy, fine-weather cumulus.

ECONOMIST: Meteorology