a-do a-fu aaaa aaab aaad aaaf aaar aaba aabb aabd aada aadu aafa aafb aafd aaff aaoo aara aard aaro aaru abaa abab abad abaf abar abau abb- abba abbb abbo abbr abda abdo abdu abff aboa abob abod abof aboo abor abou abra abro abua abud abuf adaa adab adad adao adar adba adda addd addo addr addu adfa adob adod adoo ador adra adro adua adub adur afaa afad afao afar afdb affa affo afoa afoo afor afr- afra afro afru afua afud aoba aora aorb aouf arab arad araf arar arau arba arda ardf ardo ardu arfa arfb arff arfu aroa arob arod aroo aror arr- arra arro arrr arru arua arub arud auaa audo aur- aura aurd auro baaa baad baaf baar baba babb babo babr babu bada badb badd bado badr badu baff bafo bar- bara barb bard barf baro barr baru bau- baud bauf baur bbad bbau bbbb bbdd bbdo bd-r bduf boab boad boar boba bobb bobo bobu boda bodb bodo bodu bofa bofd boff bofu boob bood boof boor bor- bora bord borf boro borr boru boua boud bouf bour brab brad braf brao brau brda brdo brfu broa brob brod broo bror brou brrr brud buad buar buba bubb bubo bubu buda budb budd budo budu buff bufo bufr bur- bura burb burd buro burr buru d-bo daab daad daar daau daba dabb dabo dabu dada dado dadu dafa daff dafo daou dara darb dard darf daro darr daru daub daud daur dbar dbfo dddd ddub dfaf dffa dfrf doab doar doba dobb dobu dod- doda dodd dodo doff doob dood doof door dora dord dorf doro dorr doru doub doud douf dour draa drab drad draf drar drau drba drda drob drod drof drou drra drua drub druu duaa duab duad duar dub- duba dubb dubu duda dudd dudo dudu duff dufu duo- dura duro duru duur faaa faad faba fabd fabo fabu fada fadd fado fafa faff fafo fara farb fard faro farr faru faud faur fbar fdoa ffar ffff ffrr foad foaf foar foba foda fofo food foof for- fora forb ford foro forr foua foud four frab frad frau frob frou frub fuad fuar fubb fubu fuda fudd fuff fufu fuor fur- fura furo furr oaau oafo oara obad obba obbo obor obra obro odbo odda oddd odoo odor odou odra odur ofdr off- offa offo offr offu ofor ofra ooaa ooba ooda ooff oooo oora oord orab orad orao orar orba orbb orbo orbu orda ordo ordu orff orfu oro- orof oror orra orro orub ouad ouff our- oura ouro ouu- raab raad raaf raba rabb rabo rabu rada radd rado radr radu rafa raff raob rara rarb rarf raro raua raub raud rauf rbaf rbbb rbbr rdfa roab road roaf roar rob- roba robb robo robu roda rodd rodo roff rofo roob rood roof roor rora roro roru roua roub roud rouf rrad rrrr ruad ruba rubb rubu ruda rudd rudo rufa ruff rufo rura rurd ruro ruru ruud uafa uaru uaua ubar ubba ubbo ubod ubra ubud udaa udad udar udau udoo udra uffa ufra uofa uofo uor- urad urao urau urba urda urdu urfa urff uro- uroa uroo urra urur uuuu