They fish sleep without close eyes. Some fish sleep during the day , and some fish sleep at night. Generally sleep through out the night.

鱼睡觉从来不闭眼的。一些鱼白天睡觉，一些鱼晚上睡觉。一般来说，鱼都是晚上睡眠的。

youdao

He began with 40 depressed patients who had been successfully lifted from their depression by a night without sleep.

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Most importantly, would they be able to sleep at night without worrying that someone might kick down the door and kill them?

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But at least we can now sleep at night without worrying that there's be a knock on the door and we'll be carted off to the army.

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