letters of credence

例句：

1. 1.The bank issued a letter of credit to the buyer.
   银行向买方出具了信用证。
2. 2.The letter of credit was good for one year from the date of issuance.
   信用证有效期为签发日起一年。
3. 3.The seller requested a letter of credit as a guarantee for payment.
   卖方要求开立信用证作为付款的担保。