They lie down under a tree and they fall asleep.

他们躺在一棵树下，睡着啦。

youdao

Dr. Sasaki found, as expected, the participants slept less well on their first night than they did on their second, taking more than twice as long to fall asleep and sleeping less overall.

佐佐木教授发现，正如预期的那样，参与者们在第一晚的睡眠质量不如第二晚，入睡所需时间是第二晚的两倍多，且总体睡眠时间也更少。

youdao

They drink too much and fall asleep.

他们喝太多而睡著了。

youdao

He is also developing light-delivering goggles that are supposed to help people reset the circadian rhythms that govern when they nod off and wake up, so they fall asleep faster and stay asleep longer.

FORBES: Who's making big bucks off your insomnia?

They were confident it was the right way to do it, despite an utter absence of evidence. (He later showed patients generally perceive less pain if bandages are removed slowly.) When patients exhausted their daily morphine rations, sometimes nurses would give them placebo injections and they would quickly fall asleep.

FORBES: Magazine Article

There are mothers and fathers who will lie awake after their children fall asleep and wonder how they'll make the mortgage, or pay their doctor's bills, or save enough for college.

NPR: Transcript Of Barack Obama's Victory Speech