bdoor bdort bo-bo bobr bodd- bodor boord boort booru borbo bordo boro- borod boroo borot borou borro borut botou botro bottu boudu bourd bouto brobo brodd brodo brood broto broud brout brrrr brud- btr-d btr-t buddu budur buord buroo burro burru burtt burud burut butdo buto- butor butot butou butuo butut d-dot d-rod ddddd do-do dobro dodoo dodro doodo doout dordt dorot dorud dotoo dotto doubt douro drbob drobo drood drott drout dtour dubbo duddo dudou durtu o-r-b obodo oboro obout obudu oddur odour odudu oduro ooooo orbot ordro orobo orodo orout ortoo oruro orutu ototo otour ottur oubut ouoro outdo outro outto ro-ro robbo robo- robor robot robrt robur rodbo rodor roodu rorbu roto- rotor rotot rotto roubt routt rubor ruutu tbtbt tbutt to-do tobor tobot tobou todor toord tordu torob torro torto tortu torud toto- totoo tourd touro trood trott trout trubu trudo truro ttttt tubo- tubod tubou tudor tudou tudur tuotu turbo turbt turot turro turtu turut tutor tutto tuuru u-dub ubobo uroob urour urubu urutu utrdb utro- utror uttur uturu ututo uuuuu