Ключевые слова: air, blue, carbon, change, chemical, chimney, climate, cloud, damage, danger, day, dioxide, dirty, ecology, effect, energy, environment, environmental, exhaust, factory, fumes, gas, global, greenhouse, hydrogen, industrial, industry, nature, outdoors, pipe, plant, pollution, power, red, sky, smog, smoke, space, stack, steam, substance, sulfide, technology, toxic, toxins, warming, white,