Complex sentence: He spent the years from 1941 to 1943 in Chongqing, China'a wartime capital, when he left China to join the Free French Army in Algiers and took part in the liberation of France in 1944.
Split into simpler sentences: He spent the years from 1941 to 1943 in Chongqing, China'a wartime capital, when he left China to join the Free French Army in Algiers. He took part in the liberation of France in 1944.