bbbb bbrg bibb bibi bibo bigb bigg bigo bigu bio- biog bioi biou birb birg biri biro birr biru bobb bobi bobo bobu bogg bogi bogo boi- boii boiu boob boog boor bor- borg bori boro borr boru bour brig brio brob brog broo bror brou brrr brug bubb bubi bubo bubu bugg bugi bugo buir buiu bur- burb burg buri buro burr buru gbbo gggg gibb gigg gigi gigo giog gioi girg giri giro girr giru giur gobi gobo gogi gogo goog gooi goor gorb gorg gori goro gorr gou- goug gour grbr grib grig grob grog groi groo gror grou grrr grub grug grui grur gubb gubi gubu gugb gugg gugi gugu guib gurb gurg guri guro gurr guru i-go ibri ibro igbo igoo igor igri iiii iiio iioi iioo iobi ioii ioio iooi iooo iorg iori ioug iri- irig irio irob irri iuiu obbo oboi obor obri obro ogb oggi ogog ogoi ogou ogri ogro ogui oigo oiii oobi oooo orbb orbi orbo orbu orgo ori- orig orio oro- oror orri orro orub ouii ouir our- ouro ouu- rbbb rbbr rgbi rib- ribo ribu rigg rigi rigo rigu riou riri rob- robb robi robo robu rogg rogi rogo roig roio roir roiu roob roog rooi roor rori roro roru roub rrrr rubb rubi rubu rugg rugi ruri ruro ruru ubbi ubbo ubii ubir uggo ugri ugro ugur uguu uirr uor- urbi urgi urgu urib uriu uro- uroo urri urur uuri uuuu