Jiangnan, 17 years old, a third-year student in the coastal S key high school; Jiang Zhaoyi, 39 years old, Jiangnan's mother and head teacher; Jiang Zhaoru, 29 years old, Jiang Zhaoyi's sister, S University lecturer, just returned to China and temporarily lived in the Jiang family. This is because ten years ago, her husband gave up all his property, including children, and moved abroad to pursue his new life. From then on, there is no news because it has nothing to do with this article for the time being, so I won't mention it for now.