정체자
The Perfection music video was released on separate dates on SM Entertainment's YouTube account, but the Chinese version has been constantly taken down due to minor typing errors in the subtitles of the early videos - the subtitle was displayed in mostly Traditional Chinese characters but a few lines also had some Simplified Chinese characters mixed in with the traditional characters. The latest video was put up on February 28, 2011 with all of the Chinese characters in the subtitles fixed into traditional Chinese characters.