Ключевые слова: blue, caution, conceptual, control, crossing, danger, direction, electric, electrical, equipment, illuminated, industry, infrastructure, journey, lamp, light, lights, line, metal, on, power, public, rail, railing, railroad, railway, red, road, safety, semaphore, sign, signal, sky, speed, station, steel, stop, stoplight, symbol, symbolical, track, traffic, train, transport, transportation, travel, urban, waiting, warning, way,