Complex sentence: The aforementioned house accommodated the three classrooms, the bathrooms and a kitchen, but was soon converted into an Assembly Hall, a sewing room and a library, after the building of new classrooms.
Split into simpler sentences: The aforementioned house accommodated the three classrooms, the bathrooms and a kitchen. But the house was soon converted into an Assembly Hall, a sewing room and a library, after the building of new classrooms.