Complex sentence: Nelson graduated from Willmar Senior High School, Willmar, Minnesota, in 1968; received a B.S. degree in Physics from Harvey Mudd College in 1972 and a M.S. and a Ph.D. in Astronomy from the University of Washington in 1974 and 1978, respectively.
Split into simpler sentences: Nelson graduated from Willmar Senior High School, Willmar, Minnesota, in 1968. He received a B.S. degree in Physics from Harvey Mudd College in 1972 and a M.S. and a Ph.D. in Astronomy from the University of Washington in 1974 and 1978, respectively.