Ключевые слова: borderline, city, concept, contagious, covid, distance, epidemic, feet, floor, health, isolation, limit, line, lockdown, message, outdoor, pandemic, pavement, people, person, prevention, protection, public, quarantine, red, risk, safe, safety, shoes, sign, social, social distancing, standing, stay, stay safe, stop, stop line, street, symbol, text, two, urban, view, virus, waiting, warning, way,