“很后悔当初”英语怎么说？

“很后悔当初”英语怎么说？

I have a great regret for what I did then.
I very much regret what I did then.
I very much regret doing so then.

i am very regret of originally

I'm really regret that I.... before

I am very regret of originally 希望采纳，谢谢啦~\(≧▽≦)/~

Regret就是这个词，若果一定要在前面加个定语“当初”的话，I regret at that time that·····