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