Complex sentence: Harry Clifton (born Henry Robert Clifton, 1832--15 July 1872) was a British music hall singer, songwriter and entertainer, whose most successful song was "Pretty Polly Perkins of Paddington Green".
Split into simpler sentences: Harry Clifton (born Henry Robert Clifton, 1832--15 July 1872) was a British music hall singer, songwriter and entertainer. A prolific songwriter, his most successful song was "Pretty Polly Perkins of Paddington Green".