Complex sentence: After returning to Cameroon, Oyono served as an ambassador to various countries from 1965 to 1974; from 1974 to 1982 he represented Cameroon at the United Nations, and from 1982 to 1985 he again served as ambassador to various countries.
Split into simpler sentences: After returning to Cameroon, Oyono served as an ambassador to various countries from 1965 to 1974. From 1982 to 1985 he again served as ambassador to various countries.