Carrie Underwood, Kara DioGuardi, Marti Frederiksen and Luke Laird co-wrote "Undo It," Underwood's May 2010 single, the third from her 2009 Play On album. The song hit No. 1 on Billboard's Hot Country Songs chart, but as Underwood explains to The Boot below, the hit's hook came about almost accidentally.

The guys had their guitars, and they were playing something kind of bluesy, and Kara's got such a great R&B sense about her. And I started "na, na, na"-ing to whatever they were playing.

And they were like, "What if that was the hook?" I said, "Aw, I don't know?" And before you knew it, we had "uh, uh, uh, uh, uh-undo it."

I mean, who would have thought? How do you write that down on paper? It was something that it didn't take that long to write, and it's so much fun to sing on stage, and people get into it. If you listen to it twice, you know all the words! We had a lot of fun with it.

We wrote "Mama's Song" and "Undo It" in the same couple of days, so it was really cool to have two completely different songs from the same group of people and the same energy going on in the same room.

This story was originally written by Donna Hughes, and revised by Angela Stefano.

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