Complex sentence: He held the seat through four successive elections until stepping down in 1980 when he was asked by then Premier of Ontario Bill Davis to serve as chairman of the Ontario Worker's Compensation Board.
Split into simpler sentences: He held the seat through four successive elections until stepping down in 1980. He resigned his seat in 1980 when he was asked by then Premier of Ontario Bill Davis to serve as chairman of the Ontario Worker's Compensation Board.