Ключевые слова: age, blue sky, clarity, cloud, clouds, deep blue sky, disease, environment, environmental pollution, forest, grass, native rock, nature, old, pollution, pollution of the environment, primeval, primeval forest, primitive times, pure, purity, rock, rocks, sea of rocks, sick tree, sick trees, sickness, sky, stone, stone age, stones, tree, trees, virgin forest, wild, wilderness,