Complex sentence: After years of labor Prosper's technique greatly evolved and he become a prominent and respected part of the local art community, but his flourishing career came to an abrupt end when he died prematurely of an asthma attack in November 1997.
Split into simpler sentences: After years of labor Prosper's technique greatly evolved and he become a prominent and respected member of the local art community. His flourishing career came to an abrupt end when he died prematurely of an asthma attack in November 1997.