Complex sentence: Canterbury RFC was formed in 1929 and when the league system was introduced in 1987 the club was placed in London 3 South East but a series of relegations saw the club playing in Kent 2 by the start of the 1990s.
Split into simpler sentences: Canterbury RFC was formed in 1929 and when the league system was introduced in 1987 the club was placed in London 3 South East. A series of relegations saw the club playing in Kent 2 by the start of the 1990s.