1. After users invest in closed-end funds, they can convert closed-end funds into open-end funds when the closed-end funds expire, and redeem them directly after converting them into open-end funds.

2. Closed-end fund investors can convert closed-end funds into open-end funds after the fund expires, and investors can purchase or redeem funds according to their net value.

3. Closed-end funds can be redeemed. Even if investors don't want to turn into open-end funds after the closed-end period, fund investors can directly liquidate the closed-end funds after they expire, and the funds will be redeemed automatically after liquidation. Or investors will postpone the fund, extend the term of the fund contract and continue to start a new round of investment.