National reunification is a sacred national tradition, ideal and belief formed by the Chinese nation for thousands of years. Since its birth, the CPC has always taken striving for national independence, people's liberation and realizing national reunification as its unswerving historical task. In the early 1980s, Comrade Deng Xiaoping, with great theoretical courage and political courage, put forward the great idea of "one country, two systems", which not only enriched and developed the Marxist theory of the state, but also set a successful example of applying the basic principles of Marxism to solve the practical problems of contemporary China. Before the "one country, two systems" policy was put forward by China, the socialist system was implemented within the unified country, and the capitalist system was implemented in individual regions according to law, which has never been seen in the past human political practice. Since its inception, "one country, two systems" has gradually become a series of principles and policies of the Chinese government towards Taiwan, Hong Kong and Macao, and has formed systematic institutional arrangements and legal provisions after the basic legal systems of Hong Kong and Macao have been established. It has also become a new political practice and governance model after Hong Kong and Macao have returned to the motherland. Practice is the only criterion for testing truth. As a new thing, "one country, two systems" has been constantly exploring and advancing in practice. Relying on the motherland, Hong Kong and Macao have implemented "Hong Kong people governing Hong Kong", "Macao people governing Macao", and a high degree of autonomy, constantly shaping their own style of modernization. Over the past 25 years since Hong Kong's return to the motherland, with the full support of the motherland, Hong Kong has withstood the impact of the Asian financial crisis, the SARS epidemic, the international financial crisis, and the COVID-19 epidemic. Its GDP has more than doubled, and Hong Kong has become the first financial center in Asia. It has the first talent competitiveness in Asia. The global financial index ranks second only to New York and London; Under the guarantee of the Hong Kong National Security Law and the "Patriot Governing Hong Kong", the major transition from chaos to governance is in the critical period of "governance and prosperity". In the past 23 years since Macao's return to the motherland, the central government has incorporated Macao into its national development strategy. From the signing of the Mainland Macao Closer Economic and Trade Relationship Arrangement in 2003 to the promulgation of the Development Plan Outline of the Guangdong Hong Kong Macao Greater Bay Area in 2019, a series of policies and measures have enabled Macao's economy to recover from negative growth for consecutive years on the eve of the return to the motherland to positive growth in 2000, and then to rank second in the world in terms of per capita GDP in 2019, Now it is ushering in the most stable period of development in history, creating a new situation of economic development. The "Macao people governing Macao" has enabled Macao along the Lingdingyang River to truly master its own development destiny. The reason why a good system has strong vitality is that it has been constantly innovated, developed and enriched, and has achieved new leaps in this process. The Fourth Plenary Session of the Sixteenth Central Committee of the Communist Party of China proposed that "maintaining the long-term prosperity and stability of Hong Kong and Macao is a new subject for the Party to face in governing the country under the new situation". The 17th National Congress was further described as "a major lesson