Play On gives Carrie Underwood a batch of superior tunes to apply her sterling vocals to, ranging from sweet folk-country numbers (“This Time,” “Quitter”) to sleek ‘n’ sassy twang-rockers (“Undo It”). Themes of gratitude (“Mama’s Song”), idealism (“Change”) and spiritual affirmation (“Temporary Home”) lend this album a positive glow. She soars mightily on the title track, infusing it with the fire of a personal credo.