Complex sentence: A new two storey rear extenstion connected to the exisiting main building will be constructed enclosing the two quad areas, one of which will be covered with on ETFE transparent roof and become the schools new dining facility.
Split into simpler sentences: A new two storey rear extenstion connected to the existing main building will also be constructed. This will enclose the two quad areas, one of which will be covered with an ETFE transparent roof and become the schools new dining facility.