Complex sentence: The community undertook the responsibility of St. John's College in the same city four years later, and when the brethren handed over the college back to the diocese in 1934, it had become a flourishing education centre.
Split into simpler sentences: The community undertook the responsibility of St. John's College in the same city four years later. When the brethren handed the college back to the diocese in 1934 it had become a flourishing education centre.