"I feel greatly benefited" 或者 "I have greatly benefited" 可以用来表达这个意思。
"benefit" 是一个英语动词，意思是"受益"，它来源于拉丁语 "benefactum"，意思是"善行"。
例句：
I have greatly benefited from studying Engpsh. (我学习英语受益匪浅)
The company has benefited greatly from the new marketing strategy. (公司因新的营销策略受益匪浅)
The community has benefited greatly from the new park. (社区因新公园受益匪浅)