Most have worked their way up from sales representatives，and they are veryproud of the role they played in the company's growth.
四级词汇讲解:
work one's way up是口语中经常用到的搭配，意为“(从底层)往上爬”，是非常形象的表达。be proud of意为“为……而骄傲、自豪”。they played in the company's growth作role的定语从句，其中短语play a rolein意为“在…中发挥作用”。
英语四级考点归纳：
短语work up在口语中经常出现，还可细化为如下搭配:
※ work sth. up意为“逐步发展;努力改进”。如:
I can't work up any appetite.我怎么也无法增加食欲。
※ work sb./oneself up(into)意为“使激动;使发怒”。如:
What are they so worked up about?他们为了什么那么激动啊?
※ work sth. up into sth.意为“使完好，修整”。如:
You should work your notes up into an esay.你应该把你的笔记整理成论文。
From:https://www.zgghmh.com/CET-4/20003669.asp