Complex sentence: Rees played in all of the first four Rugby World Cup Finals-1987,1991,1995 and 1999-retiring after the 1999 finals and becoming one of a small group of players, including fellow Canadian Al Charron to have appeared in all four World Cups.
Split into simpler sentences: Rees played in all of the first four Rugby World Cup finals, the 1987,1991,1995 and 1999. He retired after the 1999 finals and becoming one of a small group of players, including fellow Canadian Al Charron to have appeared in all the first four World Cups.