回想起来，我可能应该告诉她。

___In ___retrospect, I should probably have told her.

回想起来，这是一次难忘的经历。

___In ___retrospect, it turned out to be an unforgettable experience.

回想起来，我们最初的策略是有缺陷的。

___In ___retrospect, our initial strategy was flawed.