Ключевые слова: air, atmosphere, business, chemical, chimney, city, climate, cloud, coal, construction, contamination, damage, dioxide, dirty, dusk, ecology, emission, energy, environment, environmental, exhaust, factory, fog, fuel, fume, gas, global, industrial, manufacturing, pipe, plant, pollution, power, production, refinery, silhouette, sky, smog, smoke, smokestack, station, steam, sun, sunrise, sunset, technology, tower, toxic, urban, warming,