Complex sentence: At Kent each of the colleges was initially built with one or more "sineor Common Room" social spaces, however over the passage of time a number of the common rooms have been transformed into eateries and more formalised social areas.
Split into simpler sentences: At Kent each of the colleges was initially built with one or more "senior Common Room" social spaces. However, over the passage of time a number of the common rooms have been transformed into eateries and more formalised social areas.