if a bond or a similar investment is callable, the company or government that sold it can buy it back early (before the maturity date) at an agreed price （按约定价格）可提前赎回的◆The bond is callable after 5 years. 5 年後债券可随时提前赎回。OPPnon-callable ➡redeemable ⨁a callable bond / debenture / note / security 可提前赎回的公债／债券／票据／证券
if a company's shares are callable, they are not completely paid for and the company can require the shareholders to pay more money for them in the future （股本金）未全部缴齐的