She sank back on the pillow and closed her eyes, breathing heavily as if asleep.

她躺回到枕头上，闭上双眼，呼吸粗重，就像睡熟了似的。

《柯林斯英汉双解大词典》

The sea was quiet, as if asleep, no wind, no waves, the sea has been frozen, like a piece of thick glass, lying there motionless.

海还是安安静静的，好像睡着了一样，没有风，也没有浪，海水已经凝固了，好像一块厚厚的玻璃，平躺在那儿，一动也不动。

youdao

Sleepwalking is when your child gets out of bed and walks around as if he's awake, but he's actually asleep.

梦游是指你的孩子下了床四处走动，好像他醒着，但实际上他是睡着的。

youdao

"He was breathing as if he was asleep when I left him, " she said.

BBC: Sara Ege

When she climbed into bed, he had already turned off the light on his side, and he closed his eyes as if he were asleep.

NEWYORKER: The Swan

The player just laid there, arms and legs outstretched, as if he had fallen asleep in the midst of making snow angels.

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