你的脑电波频率变慢且变得十分有节奏，仅变慢的一点，以第一睡眠期的阿尔法节律波动，而不是更快的波率。

Your brain waves slow and become quite regular. Your brain waves slow down a bit too, with the alpha rhythm of rather fast waves 1 sleep.

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You start off with a transition period when you're falling asleep. We call that stage I.

一开始是过渡期,你开始进入睡眠状态，这是第一阶段。

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There is slow-wave sleep or "quiet sleep."

第一种是慢波睡眠，“安静的睡眠”

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