Simplify the following text for a Grade 8 native English-speaking person.
Original: Younha ( Korean Hangul : ; hanja : ; Go Yoon-ha , Japanese Katakana : ã ã ã , Yunna ) born April 29 , 1988 in Seoul , Korea , is a K-Pop and J-Pop South Korean singer .
Simplified: Younha ( Korean : ê ì í ; Hanja : é `` å æ Go Yoon Ha Japanese : ã ã ã Yunna ) , born 29 April 1988 in Seoul , Korea , is a Korean pop singer .