When you're really tired sleep is what you want to do like when you're really hungry you want to eat.

你累了，就会想睡觉,正如你饿了想吃东西一样。

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"I learned a long time ago that when you're tired you become mistake prone, " he says.

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"And never post when you're tired, emotional or drinking--that's a recipe for disaster, " she notes.

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"When you're disoriented because you're out of breath and tired and you think you're one mile away, you could be potentially three or four miles away, " Muir said Wednesday afternoon.

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