Complex sentence: Upon graduation from Sejong University with a degree in Film Arts, he resumed his acting career in 2008 and began using his agency's recommendation stage name, Yoo Yeon-seok.
Split into simpler sentences: Upon graduation from Sejong University with a degree in Film Arts, he resumed his acting career in 2008. At his agency's recommendation, he began using the stage name Yoo Yeon-seok.