Complex sentence: Gregory Stuart "Greg" Lake (10 November 1947--7 December 2016) was an English guitarist, singer, songwriter, and producer who gained prominence as a founding member of the progressive rock bands King Crimson and Emerson, Lake & Palmer (ELP).
Split into simpler sentences: Gregory Stuart "Greg" Lake (10 November 1947--7 December 2016) was an English singer, musician, songwriter, and producer. He was a member of the progressive rock bands King Crimson and Emerson, Lake & Palmer (ELP).