The central bank's purchase of foreign exchange or gold from commercial banks means that foreign exchange reserves and money supply will rise. First of all, foreign exchange refers to China enterprises exporting goods abroad, but selling things on other people's sites must have received other people's money. China enterprises want to get their money back, and pay their employees to buy raw materials to continue production. How can they get it back? The renminbi will not come out of thin air, so the liquidity in the market will increase, bank deposits will increase, and the reserves paid will also increase. The causal relationship is as follows: enterprise export-foreign exchange earning-foreign exchange settlement-central bank issuing funds-increasing market liquidity-increasing funds through banks-increasing deposits-increasing reserves. I don't know what deposit reserve is. Deposit reserve means that commercial banks deposit a certain proportion of customer deposits in the central bank to ensure a certain ability to pay.