Ключевые слова: air, art, atomic, blue, car, carbonic, change, climate, co2, conservation, deforestation, design, dirty, doodle, drawn, earth, ecology, ecosystem, environmental, exhaust, gaz, global, hand, hole, icon, impurity, industrial, industry, layer, line, oxide, pencil, planet, pollution, problem, protection, rubbish, scrap, sketch, smoke, smoulder, soil, steam, warming, water,