Ключевые слова: atom, blue, building, built, chemical, chimney, city, coal, construction, dirty, electricity, energy, environment, factory, fossil, fuel, fumes, gasoline, generation, industry, midair, modern, nature, pipe, plant, pollution, power, pump, site, sky, smog, smoke, smoking, stack, station, steam, substance, sun, supply, technology, tower, toxic, tree, turbine, up, urban, water, wealth,