Your body needs to experience all three steps of sleep—light sleep, dream, and deep sleep—to fully repair itself.

你的身体需要经历睡眠的三个步骤——浅睡眠、做梦和深睡眠——从而进行完全的自我修复。

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We experience some deep, quiet sleep and some active sleep, which is when dreams happen.

我们会经历一些深层且安静的睡眠以及一些活跃的睡眠，而活跃的睡眠时期正是做梦的时候。

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Over time, not having enough sleep—especially deep and REM sleep—can cause one to become sick more easily.

随着时间的推移，睡眠不足会让人更加容易生病，尤其是深度睡眠和快速眼动睡眠时间不足时。

youdao

Suddenly I was in deep,dreamless, peaceful sleep.

VOA: special.2010.07.10

But think of the various periods during the night in which you are in a deep, deep dreamless sleep.

但请设想你处在这样的夜晚,你处于熟睡，安枕无梦。

耶鲁公开课 - 死亡课程节选

It's not that He simply wakes up those in a deep, deep sleep.

他并不只是将他们从沉睡中唤醒。

耶鲁公开课 - 死亡课程节选

Total deep sleep decreases from nearly 20% of a normal nights sleep for those under 25 to less than 5% for those over 35.

BBC: Sleep linked to ageing

That part of the brain is essential for entering deep sleep, but with age the region degrades.

BBC: Boosting sleep 'may slow memory rot'

Early one Sunday morning, the shrill reverberating sound of my home phone woke me from a deep sleep.

FORBES: A Rolls Royce Drove My Overnight Success