"Old Things in the South of the City" was a story about her life and experiences in Suzhou, Shanghai, and other places. The main content of this book could be summarized as follows: 1. Lin Haiyin's personal experience: Lin Haiyin was born in Taiwan. She moved to Shanghai with her parents in her early years and became a doctor. She spent her childhood and youth in Suzhou and Shanghai, witnessing the prosperity and changes of the city. 2. The Old Story in the South of the City: This book narrates the characters and stories in the Old Story in the South of the City, including Suzhou's traditional culture, historical events, business culture, etc. 3. Lin Haiyin's description of the old things in the south of the city: Lin Haiyin described the old things in the south of the city in detail based on her own personal experience, including the buildings, streets, shops, culture, and people in the south of the city. 4. Description of Suzhou and Shanghai: The description of Suzhou, Shanghai and other places in this book is very vivid. It shows the history, culture, architecture and other characteristics of Suzhou and Shanghai so that readers can better understand these cities. To sum up, the book "Old Things in the South of the City" mainly described Lin Haiyin's personal experience, the old things in the South of the City, Suzhou, Shanghai and other aspects of her personal experience and memories, vividly showing the history and culture of these cities.