Complex sentence: The Albatros J.I was a "J-class" derivative of the Albatros C.XII and utilized the wings and tail of the C.XII reconnaissance aircraft while adding a new slab-sided fuselage.
Split into simpler sentences: The Albatros J.I was a "J-class" derivative of the Albatros C.XII. The J.I utilized the wings and tail of the C.XII reconnaissance aircraft, which were joined to a new slab-sided fuselage.