bbbb bbrg bibb bibi bibo bigb bigg bigo bio- biog bioi birb birg biri biro birr bivi bobb bobi bobo bogg bogi bogo boi- boii boob boog boor bor- borg bori boro borr bovi bovo brig brio brob brog broo bror brrr brvi gbbo gggg gibb gigg gigi gigo giog gioi girg giri giro girr gobi gobo gogi gogo goog gooi goor gorb gorg gori goro gorr govi grbr grib grig grob grog groi groo gror grov grrr gvvv i-go ibri ibro igbo igoo igor igri iiii iiio iioi iioo iobi ioii ioio iooi iooo iorg iori iri- irig irio irob irov irri ivbv ivig ivor obbo oboi obor obri obro obvi ogb oggi ogog ogoi ogri ogro oigo oiii oobi oooo orbb orbi orbo orgo ori- orig orio oro- oror orri orro orvr ovi- ovo- ovoo rbbb rbbr rgbi rib- ribo rigg rigi rigo riri rivo rob- robb robi robo rogg rogi rogo roig roio roir roob roog rooi roor rori roro rovi rovo rrrr vbrg vigo vigr viii virb virg viri viro virr vivi vivo voio voir voog voor vor- vori voro vrio vvob vvog vvvv