I'm sorry. For these large orders, we insist on payment by L C.
对不起。对于这样金额大的订单,我们坚持用信用证支付。
Inviting the fire brigade to put out a nonexistent fire is a crude form of deception which no self-respecting student would ever indulge in.
请消防队来扑灭一场根本没有的大火是一种低级骗局,有自尊心的大学生决不会去做。