Complex sentence: Wonik Yi entered Dae-Yeon temple at the age of five in 1964 and lived there until the age of nineteen and trained in traditional Moosul (martial arts) until he joined the South Korean Special Forces.
Split into simpler sentences: Wonik Yi entered Dae-Yeon temple at the age of five in 1964. He lived at the temple until the age of nineteen and trained in traditional Moosul (Martial Arts) until he joined the South Korean Special Forces.