Complex sentence: Harold Haley was a professional rugby league footballer who played in the 1930s, and 1940s, playing at representative level for Yorkshire, and at club level for Castleford, as a, i.e. number 9, during the era of contested scrums.
Split into simpler sentences: Harold Haley was a professional rugby league footballer who played in the 1930s, and 1940s. He played at representative level for Yorkshire, and at club level for Castleford, as a, i.e. number 9, during the era of contested scrums.