bbbb bibb bibi bibo biff bifi bio- bioi birb biri biro birr bizz bobb bobi bobo boff boi- boii boob boof boor booz bor- borf bori boro borr borz bozi bozo brio briz brob broo bror broz brrr bzzz ffff ffii ffrr fiff fifi fifo fiii fior fizz fofo foof for- forb fori foro forr frib frio friz frob frzb ibfi ibri ibro ifbb ifor ifrb ifrf ifri iiii iiio iioi iioo iobi ioii ioio ioof iooi iooo iori iri- irio irob irri izzo obbo oboi obor obri obro off- offo offr ofor ofoz oiii oobi ooff oooo oozi orbb orbi orbo orff orfi ori- orif orio oro- orof oror oroz orri orro orzo rbbb rbbr rib- ribo riff riif rioz riri rizi rizz rob- robb robi robo roff rofo roif roio roir roiz roob roof rooi roor rooz rori roro rozi rozz rrif rrrr z-ro zibo ziff ziri ziro zizi zizz zobo zoff zoio zoo- zorb zori zoro zozo zzzz