Once upon a time, in a peaceful forest, there lived a little bird named Luna. Luna loved to fly and sing with her friends. One day, while flying, Luna met a big, wise owl. The owl said, "Luna, be careful with your lung, don't fly too high or you will get hurt."
Luna did not listen to the owl. She wanted to fly higher and higher. Her friends tried to stop her, but she did not want to listen. "I can do it," she said. Luna flew so high that the sky became dark and the air became thin.
Luna's lung hurt, but she did not stop. She wanted to touch the stars. Suddenly, Luna could not breathe and she fell down. Her friends cried and said, "We told you not to fly so high." Luna closed her eyes and never woke up again. The peaceful forest was sad and quiet without Luna's songs.
