Complex sentence: From 1956 to 1958, he held various teaching and fellowship positions at international affairs colleges and institutes around Beijing before becoming a professor of international law at the Foreign Affairs College, Beijing, in 1984.
Split into simpler sentences: From 1956 to 1958, he held various teaching and fellowship positions at international affairs colleges and institutes around Beijing. He became a professor of international law at the Foreign Affairs College, Beijing, in 1984.