Dad teaches you a good way to fall sleep: Counting Sheep.

爸爸教你一个好办法入睡：数羊。

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Sleeping during the day makes it difficult to fall sleep at night.

在白天睡觉就会让我们在夜里难以入睡。

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No matter how sleep deprived an animal or human may be, it would not be adaptive for the sleep homeostat to kick in and to make the animal fall sleep when it is in the midst of a flood or forest fire.

当动物或人类面临洪水或森林大火时，不管如何缺觉，他们也不会遵从自身睡眠平衡而在这时睡着。

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Last August,a study in the journal Sleep Medicine said children who go to bed after nine o'clock took longer to fall asleep and slept less.

VOA: special.2010.06.09

Sleep thought" is the sort of thing you get typically before you fall asleep and it's like "did I take the garbage out, ??

半睡半醒的想法是指那些,你睡着前所想到的东西,例如“我倒垃圾了吗？

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Blue light suppresses production of a brain chemical called melatonin, which helps us fall sleep.

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So after Prunier I go shopping for Scotch, then I get on the plane and fall sleep.

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Tonight, somewhere in America, a young person, let's say a young man, will struggle to fall to sleep, wrestling alone with a secret he's held as long as he can remember.

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