Ключевые слова: air, blue, chemistry, cloudless, cold, contamination, day, ecology, electricity, factory, field, frosty, frozen, fuel, heat, hydroelectric, hydroelectric power plant, industry, landscape, line, manufacturing, misty, morning, ozone, pipe, pole, pollution, power, pylon, refinery, river, russia, sky, smoke, snow, steam, striped, sunlight, thermal, trumpet, water, wind, winter, zai,