How did you come up with this crazy idea? ✬

I hope you can come up with a better plan than this. ✬

I wish I could come up with a good answer to the question. ✬

I can't come up with a good idea. ✬

When did you come up with such an idea? ✬

I've just come up with a great idea. ✬

I think it wouldn't be too hard to come up with a better system. ✬

Tom hasn't come up with a good answer to the problem yet. ✬

How did you come up with that idea? ✬

It was impossible to come up with a really satisfactory solution. ✬