Many fares are valid only for the flights on the dates shown on the ticket and may not be changed at all, or only upon payment of an additional fee.

很多票价仅对客票上载明的特定日期的航班有效，并且不得变更，或者是在支付相应的费用后方可变更。

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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

The Bylaws provide for a member to leave the conference upon notice and payment of a specified fee.

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Because of this cartel, and unlike their skilled counterparts in the days of indentured servants, college athletes cannot receive a cash inducement to sign up or the promise of a cash payment upon completion of their term.

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