Basically all transactions are in pure dollars. For some large orders, the official will coordinate the US to accept a certain amount of RMB, because both China and the United States are in deficit trade (China earns more dollars), so even if the US dollar is used for settlement, the US still can't save RMB foreign exchange, which means that the US will give us money every year.

The renminbi has little international purchasing power and can only be used for trade with China, so it is useless for the United States to want renminbi. Except for a few countries that have close foreign trade relations with China, most other countries do not accept RMB. For example, the Sino-Russian oil order, worth 700 billion US dollars, was originally agreed to be half US dollars and half RMB. As a result, Russia changed its mind and insisted on all dollars. Finally, Yeltsin came forward to talk about 20% RMB.

With dollars, you can buy anything in the world. For example, the trade between China and Australia and Canada is earned by the trade between China and the United States.