Complex sentence: Sir Richard Greenbury (born 31 July 1936--September 27,2017) was chairman and chief executive of the British retailer Marks and Spencer from 1988 to 1999.
Split into simpler sentences: Sir Richard Greenbury (31 July 1936--September 27,2017) was a English businessman. He waschairman and chief executive of the British retailer Marks and Spencer from 1988 to 1999.