Complex sentence: Some GDS systems (primarily Amadeus CRS and SABRE) also have a dual use capability for hosting multiple computer reservations system, in such situations functionally the computer reservations system and the GDS partition of the system behave as if they were separate systems.
Split into simpler sentences: Some GDS systems (primarily Amadeus CRS and SABRE) also have a dual use capability for hosting multiple computer reservations system. In such situations functionally the computer reservations system and the GDS partition of the system behave as if they were separate systems.