bbbb bbdd bbdo bbox bd-r bdii bibb bibi bibo bidi bido bidr bidu bidx bio- bioi biou biox birb bird biri biro birr biru birx bixi bobb bobi bobo bobu bodb bodi bodo bodu boi- boid boii boiu boob bood boor boox bor- bord bori boro borr boru boud bour brdo brid brio brix brob brod broo bror brou brox brrr brud brux bubb bubi bubo bubu budb budd budi budo budu buid buir buiu buix bur- burb burd buri buro burr buru d-bo d-ix dddd ddub dibb dibo didi dido didu diii dior diou dird dirr diux dixi do-x dobb dobi dobu dod- dodd dodi dodo doid doix doob dood door dord dori doro dorr doru doub doud dour doux drib drix drob drod drou drub drui druu dub- dubb dubu dudd dudo dudu duid duir duo- duri duro duru duur dxbr dxdr dxii dxix dxrd dxrr dxrx dxur dxxr dxxx ibdo ibid ibox ibrd ibri ibro iddo idid idio idir idro idub iduo iiii iiio iioi iioo iobi iod- iodd iodo ioii ioio iooi iooo iori irdo iri- irid irio irix irob irod irri iuiu ixxi obbo obid obix oboi obor obox obri obro odbo oddd oddi odio odir odiu odoo odor odou odur oido oiii oobi oodi ooid oooo oord orbb orbi orbo orbu ordo ordu ori- orid orio orix oro- oror orri orro orub ouii ouir our- ouro ouu- oxi- oxid oxo- oxox oxud oxxo rbbb rbbr rdio rib- ribo ribu ridd ridi rido ridx riou riri rixo rob- robb robi robo robu rodd rodi rodo roid roio roir roiu roob rood rooi roor roox rori roro roru roub roud roux roxo rrrr rubb rubi rubu rudd rudi rudo ruid rurd ruri ruro ruru ruud ubbi ubbo ubid ubii ubir ubod ubud uddi udid udir udoo udox uirr uor- urbi urdu urib uriu urix uro- uroo urox urri urur uuri uuuu uxor xbox xibo xibu xidi xiii xixi xoro xoxo xrdb xrod xuri xuxu xxii xxix xxxi xxxo xxxx