Ключевые слова: biodegradable, cardboard, cardboard box, collection, contrast, disposal, ecofriendly, ecology, environmental, garbage, material, package, packaging, pap 21, paper, paper recycling, paperbased products, paperboard, pile, pollution, recycle, recycling, reusable, reuse, shadows, sign, sort, stack, sunlight, sustainability, sustainable, symbol, trash, waste, waste sorting, zero waste,