Complex sentence: Dennis Harris is a professional rugby league footballer who played in the 1960s, and 1970s, playing at club level for Castleford, as a, i.e. number 2 or 5.
Split into simpler sentences: Dennis Harris is a former professional rugby league footballer who played in the 1960s, and 1970s. He played at club level for Castleford, as a, i.e. number 2 or 5.