In June p>1883, Sun Yat-sen, who had graduated from the highest institution in Hawaii, returned to China by ship. After the ship entered the waters of China, it was blackmailed by the Qing tax collectors, and Sun Yat-sen further felt the corruption of the Qing Dynasty. After he returned to Cuiheng Village, he saw a China who paid exorbitant taxes and levies. The villagers are conservative, and the teaching in private schools still follows the old rules, memorizing and memorizing, with little mental enlightenment. In the first month of 1887, Sun Yat-sen was transferred to Hong Kong College of Western Medicine at the age of 21. Graduated in five years. At that time, Hong Kong was well-ordered, and bribery was unique. I also heard that Britain and Europe have excellent politics, all of which are the achievements of people's hard work. Therefore, only by changing the government can we improve society. China has only had a bad government for hundreds of years, but no good government. Therefore, after graduating from college, Sun Yat-sen decided to abandon his career as a doctor and engage in the cause of medical care. He said: "It can be seen that my revolutionary ideas are entirely derived from Hong Kong." On September 3th, 1896, Sun Yat-sen arrived in Liverpool by boat from new york. On October 1st, he went to London to meet with his teacher, Kang Deli. After that, he was followed by Qing detectives, and then he was taken to the Qing embassy in London for house arrest. Hind's teacher, Kangdeli, mobilized public opinion to save him. This is the famous "London Suffering". Sun Yat-sen's suffering in London attracted international attention and became an internationally recognized revolutionary leader in China. For personal safety, Sun Yat-sen continued to live in London and studied books on politics, diplomacy, law, military affairs, minerals and economy in the British Museum. The research and social investigation in London have greatly promoted Sun Yat-sen's thought and political proposition, and his thought of the Three People's Principles has become more complete and mature. Sun Yat-sen is a great patriot and forerunner of democratic revolution in China, but his contribution lies not only in China, but also in all mankind, so he belongs not only to China, but also to the whole world. Sun Yat-sen's thought system of the Three People's Principles is the most critical and breakthrough guiding ideology in China's political modernization movement.