Complex sentence: Sir Peter Brian Medawar OM CBE FRS (28 February 1915--2 October 1987) was a British biologist, whose work on graft rejection and the discovery of acquired immune tolerance was fundamental to the practice of tissue and organ transplants.
Split into simpler sentences: Sir Peter Brian Medawar OM CBE FRS (28 February 1915--2 October 1987) was a British biologist. Medawar's work on graft rejection and the discovery of acquired immune tolerance was fundamental to the practice of tissue and organ transplants.