lee soo-young (hangul: 이수영; born lee ji-yeon, hangul: 이지연 on april 12, 1979) is a south korean ballad singer. she debuted in 1999 with the hit album, "i believe", and quickly gained popularity due to her strong singing skills. during the mid-2000s, lee was one of south korea's best-selling singers, selling more than 700,000 albums in 2004 alone despite a recession in the music industry.