Complex sentence: The oldest composition on "Astral Weeks" is "Ballerina", which Morrison composed in 1966 while still a member of Them and about the same time he first met his future wife, Janet.
Split into simpler sentences: The oldest composition on "Astral Weeks" is "Ballerina", which Morrison composed in 1966 while still a member of Them. About the same time he first met his future wife, Janet.