The former offers the issuer the option to redeem the bonds at an earlier date, and in this case, the investor is usually paid a pre-mium over the par value to compensate for the inconvenience.

• 前者让发行机构有权在 到期日前赎回债券，在这种情形下，为了补偿持有人的不便，他取回 的金额通常会高过本金的数目。