Complex sentence: In 1924, the Red Ensign was approved for use on Canadian government buildings outside Canada, and in 1945, the flag was officially approved for use by government buildings inside Canada as well, and once again flew over Parliament.
Split into simpler sentences: In 1924, the Red Ensign was approved for use on Canadian government buildings outside Canada. So in 1945, the flag was officially approved for use by government buildings inside Canada as well, and once again flew over Parliament.