Complex sentence: He was there for two years, after which he studied at St. Mary's College, Kegalle before completing his secondary education at St Joseph's College, Colombo where he passed the Cambridge Senior exam with Honours.
Split into simpler sentences: He was there for two years, after which he studied at St. Mary's College, Kegalle. He completed his secondary education at St Joseph's College, Colombo where he passed the Cambridge Senior exam with Honours.