At the end of the loan upon your payment of the principal and of sufficient additional interest, John Milton, Sr., the goldsmith, would return to you the gold that you had entrusted to him.

在贷款期限到期时，在你支付了本金,和额外的利息后，金匠约翰弥尔顿会把你托付,给他的金币还给你。

耶鲁公开课 - 弥尔顿课程节选

Your mortgage payment is constant through time but the fraction of it that goes to paying off principal versus interest changes through time and it just changes as dictated by this formula.

抵押贷款每月还款是固定的,但是其中本金和利息的比例关系,会随时间而改变,这是由这个公式所决定的

耶鲁公开课 - 金融市场课程节选