Complex sentence: Derek Edwards is an English professional rugby league footballer who played in the 1960s, and 1970s, playing at representative level for Great Britain, and Yorkshire, and at club level for Castleford, and Keighley, as a, i.e. number 1.
Split into simpler sentences: Derek Edwards is an English former professional rugby league footballer who played in the 1960s, and 1970s. He played at representative level for Great Britain, and Yorkshire, and at club level for Castleford, and Keighley, as a, i.e. number 1.