Complex sentence: Within two years, however, Nabeshima Naomasa had renovated it and moved in, and by 1874 the castle was used as a court building and a prefectural office, and in 1883 it became a junior school.
Split into simpler sentences: Within two years, Nabeshima Naomasa had renovated it and moved in. By 1874 the castle was used as a court building and a prefectural office, and in 1883 it became a Junior school.