Complex sentence: Grandmaster Sang Chul Lee is a leading taekwondo innovator and missionary and has played an instrumental role in the promotion and development of taekwondo throughout the United States and the world.
Split into simpler sentences: Grandmaster Sang Chul Lee is a leading Taekwondo innovator and missionary. Grandmaster Lee has played an instrumental role in the promotion and development of Taekwondo throughout the United States and the world.