首先，睡眠者在半梦半醒及不同调节机制之间转换时进入睡眠状态，呼吸可能短暂地停止或减少。

First, there may be a brief cessation or reduction of breathing when falling asleep as the sleeper waxes and wanes between sleep and wakefulness and their differing control mechanisms.

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第二，一旦完全进入睡眠状态，非快速眼动期间血液中的二氧化碳增加，氧气减少。

Second, once sleep is fully obtained, there is an increase of carbon dioxide and a decrease of oxygen in the blood that persists during NREM.

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然后它将进入睡眠状态，并等待下一次构建时间。

It then goes to sleep and waits for the next time to build.

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