If the new One Direction single, "Live Like We're Young" sounds familiar--it should.  Because they admittedly copied a legendary riff from the Clash's song, "Should I Stay or Should I Go."

1D's Harry Styles says about the song, "It's kind of on purpose. It's a great riff. It also sounds a lot like 'Summer Nights' from the film 'Grease'."

Take a listen to the  One Direction song here:

and the Clash: