She once told me more or less the same thing.

A girl I knew once told me all about them.

A friend once told me you can only really do two things well at any one time.

I'll tell you what an old man once told me.

Knew it from something his mother had once told him.

"Someone once told me that a long time ago, and I believe it now more than ever."

But I once told you direct action isn't always the best response.

My father once told me that the most important thing every man should know is what he would die for.

Something that my sister once told me came to mind.

He once told me not to be afraid as my death was many years off and would come in a way I least expected.