เสียงที่ใช้ร่วมกัน

No.1....................Sora lives in Seoul and cares about the environment. One day, she noticed that her classroom used too much paper. Many students threw away paper after using it only once. Sora suggested using both sides of the paper. She also made a box to collect used paper for recycling. Her classmates liked her idea and started to follow it. Now, they use less paper and produce less waste. Sora feels happy that her small idea helped her class.