On the basis of comprehensive analysis of the international and domestic situation and China's development conditions, the 19th National Congress of the Communist Party of China made it clear that building a socialist modern country in an all-round way can be arranged in two stages. By 2020, we will resolutely fight the battle against pollution; By 2035, the ecological environment will be basically improved, and the goal of a beautiful China will be basically achieved. In the first stage, from 2020 to 2035, on the basis of building a well-off society in an all-round way, we will struggle for another fifteen years and basically realize socialist modernization. In the second stage, from 2035 to the middle of this century, on the basis of basically realizing modernization, we will strive for another fifteen years to build China into a prosperous, strong, democratic, civilized, harmonious and beautiful socialist modernization power.