When a baby is put face down in a bed, it begins to re-breathe carbon dioxide, which is toxic.

VOA: standard.2010.02.08

But if you're the type who prefers to be bed by midnight, that's quite okay too; there'll be plenty of time to work on the project.

但是，如果你习惯半夜睡觉，也同样可以,你还有足够的时间完成这个项目。

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