Sleepwalking happens during deep sleep.

梦游发生在深度睡眠期间。

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It usually happens in the first few hours of sleep in the period called deep sleep.

它通常发生在睡眠的最初几个小时，这个阶段被称为深度睡眠阶段。

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This was during the first deep sleep period, the researchers said.

研究人员说，这发生在第一次深度睡眠期间。

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Suddenly I was in deep,dreamless, peaceful sleep.

VOA: special.2010.07.10

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。

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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。

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

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

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But most business-class beds aren't wide enough for deep sleep because passengers can't change positions without waking up.

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