That suggests that catch-up sleep may undo some but not all of the damage that sleep deprivation causes, which is encouraging, given how many adults don't get the hours they need each night.

这表明补觉可以弥补部分但不是全部睡眠缺乏造成的损害，考虑到有很多成年人每晚都没有得到他们所需的睡眠时间，这令人鼓舞。

youdao

How many hours do you sleep every night?

你每天晚上睡几个小时？

youdao

Then how many hours of sleep should junior high school students get a night? The answer is nine.

那么初中学生每晚应该睡多少个小时呢？答案是9小时。

youdao

How many of you did not bring the passages that I sent to you by e-mail last night?

你们中有多少人没有带讲义,我昨晚用邮件发给你们的？

耶鲁公开课 - 文学理论导论课程节选

While 40 residents were evacuated on Friday night, it is not clear how many had to leave their homes on Saturday night.

BBC: Denbigh homes evacuated by explosives experts

One thing we noticed at this party, besides the fact that even the waitresses looked like recognizable actresses (one Selma Blair, another Ginnifer Goodwin) was how many people go out at night and just take pictures.

WSJ: Tribeca's Expanding Calendar

The question is how many other animals might use similar night-time navigation.

BBC: Dung beetles guided by Milky Way