In fact, the early redemption clause means that the bond issuer can redeem the bond before the bond expires. This early redemption clause will cause reinvestment risk for pure bonds (that is, the bond is not embedded with derivatives), because the early redemption is likely to be a major change in the market financing cost, in short, the market interest rate has decreased. It turns out that the interest rate paid when the bond is issued is higher, and the issuer can use the redemption price in the redemption clause to measure the amount of benefits from reducing the debt cost. If there are embedded derivatives in bonds, such as convertible bonds, it can generally trigger the early redemption clause. In most cases, the underlying securities will exceed the conversion price. Generally, as long as you convert bonds into stocks, the repayment risk of bonds will be relatively reduced.

the sinking fund clause means that the bond issuer should withdraw a certain amount as a fund to guarantee the repayment of debts. Generally, the existence of this fund will reduce the repayment risk of bonds.