Complex sentence: The school's population is just under 700 students, aged between 5 and 18 years; it was founded in 1929 by the school benefactor Baroness Strickland, Countess della Catena, who gave a generous gift to establish the college.
Split into simpler sentences: The school's population is just under 700 students, aged between 5 and 18 years. It was founded in 1929 by the school benefactor Baroness Strickland, Countess della Catena, who gave a generous gift to establish the college.