There's certainly no fixed maturity date: Money shows up in irregular chunks as people pay down their mortgages at unpredictable times-for instance, when they decide to sell their house.

而且没有固定的到期日：几时能收回钱是不知道的，因为人们支付他们的抵押贷款时间是不可预测的，这个时间举例来说，当他们决定出售他们的房子的时候。

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The fact that early bonds had no fixed maturity date ensured that any change in interest rate was fully reflected in the capital value of the bond.

ECONOMIST: What did early 19th-century literary characters live on?