Subtitles section Play video Print subtitles [MUSIC PLAYING] ONE DIRECTION: This letter's "U." You know it's true. It starts some words. There are more than a few-ew-ew. LOUIS: U starts uh, and ugh and up. U starts udon. There's some in this cu-u-up. HARRY: 26 letters are in the alphabet. But we're here to sing about U. ONE DIRECTION: U, you begin the word ukelele. U, there's a UFO flying by me. U, and you're gonna feel so unhappy. I love U, ooh-ooh. U, you know so you're useful. U, for unique. That's a unique gown. U, check it out, Elmo's upside-down. U, there's a unicorn dressed as a clown. Letter U-u-u. That's what makes you so useful. Ooh-ooh. HARRY: That's what makes you so useful. ZAYN: Don't get upset. U's what you get. And when you swim underwater, you're we-e-et. NIALL: U starts urn. That's what I've learned. And a unicycle taught to t-uh-urn. HARRY: 26 letters are in the alphabet. But we're here to sing about U. ONE DIRECTION: U, for utensils in Grover's hands. U is for uncles, but not for aunts. U, there are U's on those underpants. Letter U-u-u-- that's what makes you so useful. Ah-ah-ah. [CONTINUES_] U, you're the ultimate. Come take a bow. U, there are artists under that cow. U, check it out. It's Bert's unibrow. Starts with U-u-u. U, you know you're so useful. Ooh-ooh. That's what makes you so useful. Ooh-ooh. HARRY: That what makes U so useful. SINGER IN VIDEO: [SINGING], You sing a song, and you be a great dancer. You dunk a ball, and you make the right letter. Everything you do, you do it better. This is what you get. 'Cause this is what you get. 'Cause this is what you get-- with the power of yet.