Don't worry. Just leave. They will call you and offer a middleprice.
还一个五分之一的价格——他们也许会生气或者是假装不想卖给你。
2
Ponders: graduate student's three years graduate the work for three years with the undergraduate student, the middleprice difference is how many.
细想一下：研究生的三年和本科生毕业工作的三年，中间的差价是多少。
3
Finally, this article specially analyzes two serious questions of "the middleprice difference" and the transaction fund security and puts forward the corresponding proposal and countermeasure.