I think you have a misunderstanding on this issue. First of all, RMB is not an international currency, and its circulation is limited to China and some neighboring countries. China's trade with other countries is generally settled in US dollars, so it cannot be said that RMB is exchanged for US dollars. Secondly, China's foreign exchange mainly depends on the accumulation of foreign trade. China relies on the advantage of cheap goods, and its exports far exceed its imports, so it has accumulated a large trade surplus, while international settlement generally uses US dollars, so foreign trade enterprises in China have accumulated a large amount of US dollars. These enterprises need RMB for their daily expenses, so they will convert the earned US dollars into RMB, which will actually make these US dollars become the wealth and foreign exchange of the country. After long-term accumulation, China has 200 million US dollars of foreign exchange reserves, and the required RMB is issued by the central bank.