Ключевые слова: abstract, bicycle, bio, biology, building, city, cloud, concept, conservation, creative, design, earth, eco, ecological, ecology, ecosystem, energy, environment, environmental, forest, friendly, globe, grass, green, idea, illustration, leaf, natural, nature, paper, planet, plant, postcard, protection, recycle, reduce, responsibility, reuse, save, savings, sign, solar, sun, template, think, together, tree, world,