Ключевые слова: ahead, alert, attention, background, black, caution, classic, concept, control, cross, crossing, danger, design, element, forbidden, icon, illustration, intersection, isolated, junction, no, object, obstacle, pictogram, rail, railroad, railway, road, round, route, safety, set, sign, silhouette, stop, street, symbol, track, traditional, traffic, train, transport, transportation, usa, warning, way, white, yellow, yield,