No one has come up with a better idea since then.

My mother was in love with the idea of America.

She might have even come up with the idea in the first place.

They came up with the idea, what did the form teacher do?

Coming up with the idea turned out to be the most difficult part.

The son was still coming to terms with the idea.

You want to be the first to come up with the idea.

By 1997, other people had come up with the same idea.

Will you come up with an idea how to do it?

You've come up with an idea on how to make yourself big money.