Ключевые слова: adult, air, asian, background, bad, care, chemical warfare, city, cough, desulfurization, disease, downtown, environment, face, female, flu, gas, girl, global warming, head, headache, health, human, illness, infection, influenza, mask, medical, one, outbreak, people, person, pollution, portrait, prevention, problem, protect, protection, protective, quality, safety, sick, smog, toxic, urban, virus, weather, woman, young,