Complex sentence: James Robinson was an English professional rugby league footballer who played in the 1930s, 1940s, and 1950s, playing at representative level for England, and at club level for Castleford, as a, i.e. number 3 or 4.
Split into simpler sentences: James Robinson was an English professional rugby league footballer who played in the 1930s, 1940s, and 1950s. He played at representative level for England, and at club level for Castleford, as a, i.e. number 3 or 4.