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。

youdao

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。

耶鲁公开课 - 心理学导论课程节选

Though the talk was highly anticipated and the room was at capacity before Williams took the stage at 2 pm, halfway through the presentation people began losing interest, falling asleep and then making their way to the exit.

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