Ключевые слова: air, brown, building, chimney, danger, dioxide, dirty, electricity, energy, environment, environmental, factory, fog, fumes, gas, generation, global, grunge, hot, industrial, industry, light, manufacturing, pipe, plant, pollution, power, problem, risk, safety, saving, sky, smog, smoke, station, steam, sunbeam, sunlight, sunset, technology, warming, yellow,