If you want to be rich, build roads first, have fewer children and plant more trees. Have fewer children, have good children and live a happy life. These two simple slogans embody a national policy of our country, you know. Family planning, the trend of population growth in China and its possible consequences, China's GDP ranks in the top ten in the world, but its per capita GDP is several hundred. It is conceivable that an overpopulated country will bring pressure on employment, housing and traffic safety, which is not good for long-term development. Therefore, we must adhere to sustainable development and turn a big country of manpower into a big country of talents.