Super Junior's Leeteuk revealed that he couldn't sing a song from beginning to end on the August 15 episode of 'Star King'.

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On the episode, 7-year-old "cup song" specialist Kang Min Chan featured as a guest, and he asked Leeteuk to sing a song to help him with his performance. The talented Kang Min Chan asked, "Do you know a song from beginning to end," and Leeteuk responded, "That's going to be hard."

Check out Leeteuk, the cup performance, and more in the episode below!