Money funds don't need fixed investment, but buy as much as they have. This is a floating guaranteed income. Generally, the average annual income is similar to that of time deposit, but it takes four days to get in and out. Some banks also have T+0 wealth management products, which are more convenient. If you want to make a fixed investment, it is recommended to buy an index fund, so that you don't have to worry about rat warehouses, stepping on mines, and fund managers are confused, and you don't have to worry about stepping on the air.