Ключевые слова: alert, bell, business, caution, change, clear, clouds, cross, crossing, danger, direction, flash, flashing, gate, go, horn, isolate, isolated, isolation, light, lights, locomotive, mainline, pole, rail, railroad, railway, railyard, red, road, roads, route, safe, safety, sign, signal, signs, sky, stop, stripe, switch, track, tracks, traffic, train, transport, transportation, travel, warn, warning,