Complex sentence: Maarten' t Hart (Maassluis, November 25,1944) is a Dutch biologist who studied zoology and ethology at the University of Leiden and taught that subject before becoming a full-time writer in the 1980s.
Split into simpler sentences: Maarten' t Hart (Maassluis, November 25,1944) is a Dutch biologist and author. He studied zoology and ethology at the University of Leiden and taught that subject before becoming a full-time writer in the 1980s.