Although most couples in rural areas in China have more than two children, almost all young people work in cities. Therefore, young high-quality immigrants will continue to hedge the elderly population in large cities, making the population age relatively lower or flat. The vitality of the big cities will be maintained. In some places, the support of the elderly in the countryside has become apparent, and may even become the norm. Japan's remote countryside is a lesson learned. This text states:. ["China's population aging problem is as serious as Japan's.", 'Rural may enter the age of aging earlier than the metropolis.', 'Demographic conditions directly determine the development of an area.', 'Population mobility will exacerbate the uneven development of urban and rural development.']