Complex sentence: He remained semi-comatose for the 9 years preceding his death in 1984, at the age of 49; he was deemed conscious but incapacitated in early June, 1976.
Split into simpler sentences: He remained semi-comatose for the 9 years preceding his death in 1984, at the age of 49. He was deemed conscious but incapacitated in early June, 1976.