Ключевые слова: 30, advice, black, blue, car, caution, color, concept, control, danger, fear, highway, icon, idea, illustration, isolated, law, limit, marker, message, mix, object, octagon, outside, overtake, penalty, red, restriction, road, roadside, roadsign, safety, shinny, sign, sky, stop, street, symbol, traffic, traffic sign, transportation, two, vehicle, warning, white,