NEED HELP to revise this paragraph，THX！ "悬壶济世" is a Chinese idiom, means treat diseases and save people. There is a legend behind it. Once upon a time, a serious disease spread in a country and many people died. One day, a magical old man came and opened a traditional Chinese medicine shop. He hang a medicinal gourd in the front door, which contained traditional Chinese medicine pills. He distributed the pill to people who needed and cured them. So later generations used hanging gourds at the door as a symbol of traditional Chinese medicine.