Complex sentence: Kerzin did his residency at Ventura County Medical Center, California and practiced medicine at the Family Practice Clinic he founded in Ojai, California for seven years, then he was appointed Assistant Professor of Medicine at the University of Washington in Seattle from 1985 to 1989.
Split into simpler sentences: Kerzin did his residency at Ventura County Medical Center and practiced family medicine in Ojai, California for seven years. He was appointed Assistant Professor of Medicine at the University of Washington in Seattle from 1985 to 1989.