In the mornings the sky appeared a heavy shade of mottled grey.

清晨，天空看上去是斑驳的深灰色调。

《柯林斯英汉双解大词典》

Some heavy clouds, swept from the sky by a rising wind, had left the moon bright.

一阵狂风吹过，吹散了天空中密布的乌云，皎洁的月亮露了出来。

youdao

The sky over the city was overspread with a heavy smog.

城市上空罩上了一层烟雾。

《新英汉大辞典》

As the sun hung heavy in the sky, we descended into a valley to find four napping lionesses guarded by two fierce males, their wild manes glowing orange, then amber as the sun set.

BBC: The Serengeti in the off-season

The sky was clear and the sun shone brightly on a heavy snow pack, but it was cold and the wind was blowing.

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