Complex sentence: Continuing on part-time status with night and correspondence courses, he graduated with a B.A. in 1969, and (after two-years in the US Army), a pre-med master's in microbiology and nutrition in 1973.
Split into simpler sentences: Continuing on part-time status with night and correspondence courses, he graduated with a B.A. in 1969. Afterward, he completed a pre-med master's in microbiology and nutrition in 1973.