Complex sentence: In 1965, the wing of Saint-Cyr was completely reworked, the dormitory of the great disappeared, a level of laboratory of physical sciences and three levels of classes and laboratories of natural sciences were constructed.
Split into simpler sentences: In 1965, the wing of Saint-Cyr was completely reworked. The dormitory of the great disappeared and a level of physical science laboratories and three levels of classes and natural science laboratories were constructed.