Only Thirty is a novel about the plight of a 30-year-old woman, including the following: 1. Marriage problem: The protagonist of the novel, Zhong Xiaoqin, faced a marriage crisis at the age of 30. Her husband had no feelings for her and had an illegitimate child with someone else. 2. Professional problems: The protagonist Gu Man in the novel also encountered difficulties in her career. Her company laid off employees and she could not find a suitable career development direction for herself. 3. Family problems: Xu Huanshan, the protagonist of the novel, also faced family problems. His parents did not agree to their marriage and his younger brother was also sick and needed to be taken care of. 4. Financial problems: The protagonists in the novel, Zhong Xiaoqin and Gu Man, also have financial difficulties. They need to pay the mortgage and also need to pay for living expenses and milk powder for their children. 5. Personal growth problems: The protagonists in the novel also face personal growth problems. They need to face the differences between their past and present and learn to accept and change. These difficulties reflected the challenges faced by 30-year-old women in life, including marriage, career, family, economy and personal growth.