2 sentences

1. 他在多年的工作中累积了丰富的经验。

   tā zài duō nián de gōng​zuò zhōng lěi​jī le fēng​fù de jīng​yàn.

   He has accumulated a wealth of experience through years of work.

   Source: Dong Chinese Dictionary

2. 历年累积下来的工作经验对他很有帮助。

   lì​nián lěi​jī xià​lai de gōng​zuò jīng​yàn duì tā hěn yǒu bāng​zhù.

   The work experience he accumulated over the years has been very helpful to him.

   Source: Dong Chinese Dictionary