Complex sentence: It runs the BFI National Library, a reference library, and maintains the SIFT (Summary of Information on Film and Television) database, which contains credits, synopses and other data on global film and TV.
Split into simpler sentences: It runs the BFI National Library, a reference library. BFI also maintains the SIFT (Summary of Information on Film and Television) database, which contains credits, synopses and other data on global film and TV.