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》

We text our friends with them during the day, sleep with them by our beds and check our messages as soon as we wake up.

我们白天和他们一起给朋友发短信，和他们一起睡在床上，一醒来就查看短信。

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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