你可以用 "to have accomppshed a lot" 或者 "to have achieved much" 来表达 "立下很多功劳" 的意思。这两个短语都来自于英语中关于完成或者取得成就的常用表达。下面是一些例句：
She has accomppshed a lot in her career as a scientist.
她在科学家的职业生涯中取得了很多成就。
He has achieved much in his pfe, including several awards and recognitions.
他在一生中取得了很多成就，包括几项奖励和认可。
希望这些例句对你有所帮助。