Ключевые слова: background, biohazard, bus, calendar, care, chalk, chalkboard, classroom, college, coronavirus, covid19, danger, dangerous, disease, distance, education, epidemic, flu, health, home, homework, ill, illness, infection, infectious, influenza, learning, length, medical, medicine, outbreak, pandemic, prevent, prevention, protect, protection, protective, quarantine, safety, sarscov2, school, separation, sick, sign, student, studying, virus, warning,