His first sleep after those 11 days lasted just 14 hours.

在这11天之后，他的第一觉只睡了14小时。

youdao

Shall I cut first, or shall I sleep first?

我该先割，还是先睡？

youdao

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。

youdao

But here is something that scientists now know: A team led by Professor Fu has reported the first genetic link to how much sleep we need.

VOA: special.2009.08.26

Well, first there's a distinction, a distinction between real dreams versus sleep thought.

首先，我们要区分，真正的梦和半睡半醒的想法。

耶鲁公开课 - 心理学导论课程节选

First of all,notice the obvious point that sometimes people die in their sleep,unexpectedly.

首先，有时人是在睡梦中无预兆地死去。

耶鲁公开课 - 死亡课程节选

"It is my fourth visit to Japan and it is the first timeI sleep well, " Waseige said.

BBC: Belgians shake off injuries

By the 1920s the idea of a first and second sleep had receded entirely from our social consciousness.

BBC: The myth of the eight-hour sleep

Ekirch found that references to the first and second sleep started to disappear during the late 17th Century.

BBC: The myth of the eight-hour sleep