They sleep by day and hunt by night.

他们白天睡觉，夜晚捕猎。

《牛津词典》

Nocturnal animals sleep by day and hunt by night.

夜间活动的动物白天睡觉晚上猎食。

《牛津词典》

youdao

A new mother,for example, quickly learns to try to sleep when her baby is quiet, even in the middle of the day.

VOA: special.2010.01.31

Probably the best answer is our body is worn out during the day and sleep is necessary to put it back into shape.

最佳的答案应该是,一天下来，我们的身体已经疲惫了,有必要进行睡眠，以恢复状态。

耶鲁公开课 - 心理学导论课程节选

Every day of the semester say it before you go to sleep.

这学期每天入睡前都要读。

耶鲁公开课 - 新约课程节选

They had been planning to attend political training classes and participate in group activities during the day and sleep in tents at night, he said.

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Observing 25 infants aged 4 to 10 months in a five-day inpatient sleep training program, researchers monitored levels of the stress hormone cortisol in the babies, who were left to cry themselves to sleep without being soothed.

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But I would leave every day and just sleep there at night.

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