Cover mouth and nose when caring for the ill person. Masks can be bought commercially or made using the readily available materials as long as they are disposed of or cleaned properly.

护理病人时掩住口鼻。可从店里购买口罩，或者使用现成材料自己制作，只要可加以适当清洗。

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Find something wet to cover your nose and mouth.

找一些湿的东西遮住你的鼻子和嘴。

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The best way is to cover your nose and mouth with a wet towel.

最好的方法是用湿毛巾捂住口鼻。

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The idea is to use the scarf to cover your mouth and nose when around others who may be ill, or to sneeze into it so pathogens will be killed instead of lingering to infect others, the site recommends.

WSJ: Keeping Cold and Flu Germs Out