Ключевые слова: background, book, branch, bright, cherish, concept, conceptual, earth, eco, ecological, ecology, education, environment, environmental, fir, found, fresh, green, ground, grow, growing, growth, idea, isolated, knowledge, leaf, learn, life, light, lone, lonely, natural, nature, one, pine, plant, planting, protection, read, reading, sapling, seedling, spring, springtime, stem, study, summer, sustainability, tree, white, young,