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甲型H1N1流感,使口罩再次走俏。大街上,戴口罩的人越来越多了。戴口罩的好处是,保护自己,免遭病毒侵袭;另一个好处是,保护别人,防止因
H1N1 influenza, masks once again popular. The street, more and more people wearing masks. The benefit of wearing a mask is to protect yourself from viruses; another benefit is protecting others and preventing