Ключевые слова: air, chemical, clean, color, company, construction, cool, cooling, day, electricity, energy, engine, engineering, environment, factory, fuel, gas, global, heat, hose, image, industrial, industry, iron, liquid, mechanical, metal, network, oil, outdoors, outside, paint, photograph, pipe, plant, pollution, power, production, refine, roof, rust, sky, smoke, steam, steel, technology, tower, warming, water, working,