Complex sentence: The song has been performed on "American Idol" by Justin Guarini, on December 15th, 2010 on Season 2, Episode 4 of "The Sing-Off" by Committed (group), Trenyce, Leah LaBelle, Joseph Murena, and Elise Testone.
Split into simpler sentences: The song has been performed on "American Idol" by Justin Guarini. It has also been covered by Trenyce, Leah LaBelle, Joseph Murena, and Elise Testone.