Ключевые слова: air, atmosphere, background, blue, chimney, city, climate, cloud, coal, construction, day, dioxide, dirty, ecology, electric, electrical, electricity, emissions, energy, environment, environmental, exhaust, factory, fuel, fumes, gas, hydroelectric, industrial, industry, landscape, petroleum, pipe, pipes, plant, pollution, power, sky, smog, smoke, smokestack, smoking, station, steam, sun, technology, thermal, tower, toxic, vapor, white,