简单的国际商务英语词汇商贸 （电子商务、海关） "advancement, payment on account" 垫付 "bottleneck" restrictions 瓶颈制约 "fair, meeting" 洽谈会 "off-grade goods, rejects" 等外品 "subunderwriting, distribution" (产品）分销 "two-for-one offer, buy one get one free" 买一送一