Complex sentence: James Joseph "Jim" Harbaugh (born December 23,1963) is a former professional football player, a quarterback in the National Football League, and is currently the head coach of the NFL's San Francisco 49ers.
Split into simpler sentences: James Joseph "Jim" Harbaugh (born December 23,1963) is a former professional football player for the National Football League (NFL). Harbaugh was a quarterback in the National Football League, and is currently the head coach of the NFL's San Francisco 49ers.