Ключевые слова: air, atmosphere, chemical, chimney smoke, chimneys, cleanliness, climate, cloud, contaminate, contamination, damage, dirty, ecology, emission, emit, energy, environment, environmental, factory, fumes, gas, global, greenhouseeffect, human, industrial, industry, landscape, ozone, pipe, poison, polluting, pollution, problem solving, reflection, river, seascape, silhouette, sky, smog, smoke, smokestack, steam, sunrise, sunset, technology, toxic, warming, water,