bo-bo bobr bonon bonou bonut boont boorn boort booru borbo born- borno bornt bornu boro- boron boroo borot borou borro borun borut boton botou botro bottu botun bourn bouto brobo bronn bront broon broto broun brout brrrr brunn bruno brunt bruun btr-t btron bubon bunun bunut buono burn- burnt buron buroo burro burru burtt burun burut butno buto- buton butor butot butou butuo butut nnooo no-no nobob nobuo nobut non-u nonno nonot noonu noort norbu noron norro nortt norun notno noto- noton notto nourt ntoro nu-nu nunon nunun nuoro nurun nuton o-bon o-r-b oboro obout onont onoon onorn onoto onour onout onto- ontoo ontur ooooo orbot ornon ornot orobo orono orout orton ortoo oruro orutu otono ototo otour ottur oubut ouoro ourno outon outro outto ro-ro robbo robo- robon robor robot robrt robun robur ronno ronto rorbu roto- roton rotor rotot rotto rotun roubt rount routt rubon rubor runo- runon runto ruutu t-nut tbtbt tbutt tntnt tobon tobor tobot tobou tonbu tono- tonto torob toron torro torto tortu torun toto- toton totoo tourn touro trono troon trott trout trubu truro ttttt tubo- tubon tubou tunon tuotu turbo turbt turn- turno turnt turnu turon turot turro turtu turut tutor tutto tutun tuuru ubobo unnun unnur unnut unoor unorn unrun unurn uroob urour urubu urutu utro- utror uttur uturn uturu ututo uuuuu