Ключевые слова: cheerful, child, childhood, children only, cleaning, ecosystem, environment, environmental conservation, ethnicity, friendship, garbage, group of people, holiday event, learning, nonprofit organization, outdoor pursuit, outdoors, people, preschool, public park, recycled material, recycling, schoolboy, schoolgirl, selfless, social issues, social services, student, studying, sustainable lifestyle, thailand, variation, volunteer, waste management,