溺れかけた私を助けてくれた彼は、命の恩人です。
He saved me when I was about to drown; I owe him my life.
恩師は私にとって人生の恩人だ。
My former teacher is a benefactor in my life.
会社が倒産しかけたとき、資金を出してくれた恩人がいた。
When the company was on the verge of bankruptcy, there was a benefactor who provided the funds.