Taylor Swift and Zac Efron Deny Relationship, Sing Together on The Ellen DeGeneres Show.

Taylor Swift and Zac Efron appeared on The Ellen DeGeneres Show Tuesday to promote their new animated movie, Dr. Seuss' The Lorax, in theaters March 2. During the interview, Taylor cleared up rumors she and Zac are in a relationship. "We are not a couple," Taylor told Ellen. "He is awesome. We are not a couple though." Taylor says it was really improbable that she and Zac would fall in love on the set since The Lorax was animated. She joked about it saying, "Like, 'Oh my God, as we were recording our voiceovers on separate coasts, we really connected.” Taylor and Zac are good friends though, and she even taught him how to play the Foster the People hit "Pumped Up Kicks" on guitar. The co-stars performed the song for Ellen, but then changed the words up to talk about some of the weird pranks Ellen has played on them over the years.