Complex sentence: Mieczysław graduated from Warsaw Technical University in 1929, worked for Polish Ministry of Military Affairs (1931-1939), than moved to France in 1939, since 1942 lived in Canada and the U.S., and finally settled in the U.S. in 1956.
Split into simpler sentences: Mieczysław graduated from Warsaw Technical University in 1929 and worked for Polish Ministry of Military Affairs (1931-1939). After 1942 he lived in Canada and the U.S., and finally settled in the U.S. in 1956.