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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