Yes, the fixed investment fund can set its own time limit and amount, just according to your own situation and preferences. Open-end funds operated by fund managers and kept by fund custodians specialize in investing in low-risk money market instruments. Different from other types of open-end funds, they have the characteristics of high security, high liquidity, stable income and "quasi-savings". The investment scope of money market funds is all varieties with high safety factor and stable income, so for many enterprises and individuals who want to avoid the risks in the securities market, money market funds are a natural haven. Under normal circumstances, you can get higher income than the interest on bank deposits, but the money fund can't guarantee the safety of the principal. (But in fact, due to the nature of funds, money funds rarely lose their principal in reality. Generally speaking, money funds are regarded as cash equivalents. )