proerrorforma invoice怎么翻译

proerrorforma invoice怎么翻译 刚刚接触信用证,怕弄错,下面条款麻烦解释一下,+commercial invoice in 1 original and 7 copies issued ,dated,signed and stamped by beneficiaries,certified in accordance with proforma invoice number bt110601 dated may 15,2011.the invoic