Complex sentence: His parents were James Gunn, a long-distance lorry driver, and Jessie Sinclair, a canteen worker at the Dounreay nuclear power plant; the pair had married despite being on opposite sides of a family feud stretching back to the 16th century.
Split into simpler sentences: His parents were James Gunn, a long-distance lorry driver, and Jessie Sinclair, a canteen worker at the Dounreay nuclear power plant. James and Jessie had married despite being on opposite sides of a family feud stretching back to the 16th century.