Ключевые слова: black, blue, business, canada, car, cargo, cars, commerce, crude, curve, ethanol, gas, industrial, industry, line, lines, metal, motion, moving, oil, pattern, pipeline, rail, railroad, railway, repetition, rural, saskatchewan, shadow, shipping, sky, storage, tank, tank car, tanker, tankers, tanks, track, tracks, trade, train, transport, transportation, water,