回复：波老师能不能讲讲英语，教一下可以说些什么？

Well, it’ll be hard for me to provide any helpful advice for this particular case since it is circumstantial. However, it looks unlikely that their sales force would prefer external contractors to their internal resources unless they had to. It is imperative for any sales or application engineer to proactively support the frontline sales who brings back the business. Nevertheless, for English learning and career development, it might be worth having a look at  英语学习 where you may find something useful.