Complex sentence: After 18 years of meritorious service under the Pakistani flag, he retired from the Pakistan Navy in 1965 as a Commander.After that, he served as principal of Cadet College Petaro from 1968 to 1972.
Split into simpler sentences: After 18 years of meritorious service under the Pakistani flag, he retired from the Pakistan Navy in 1965 as a Commander. Later, he served as principal of Cadet College Petaro from 1968 to 1972.