We insisted on payment by a confirmed, irrevocable letter of credit.

我们用保兑的，不可撤消的信用证为付款条件。

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Our terms of payment are by a confirmed irrevocable letter of credit by draft at sight.

我们的支付方式是以保兑不可撤消的、凭即期汇票支付的信用证。

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This letter is about a counter-offer, asking for easier payment terms, e. g. cash against documents on arrival of goods instead of by confirmed, irrevocable letter of credit.

这是一封有关还盘的书信，要求得到较宽的支付条款。例如，货到后凭单付款，而不是凭保兑的、不可撤销的信用证付款。

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In the case of insured bonds, where the interest payment is funded by a bond insurer or letter of credit issuer, the default is still the same.

FORBES: Even If A Bond Doesn't Default, You Can Still Lose Your Money