b-r-k bbook bo-bo bobko bobok bobr bokko bokok bokor booko bookz boort booru borbo borko borku boro- borok boroo borot borou borro bortz borut borzu botok botou botro bottu bouko bouto bozok bozoo brobo brook broto brouk brout brrrr bruzz btr-t bukk- bukor buroo buroz burro burru burtt buruk burut butko buto- butor butot butou butuo butut buzuk buzzr bzzzt k-rob k-t-b ko-ko kobru kobuk kobuz kokko kokor kokot kokou kokur kokut kooru korbo korku koror korro kortu koruk kotor kotto kottu kotur kouto kozub kroot krotz krout krtok kruto kubok kukko kukok kukur kurbu kurku kurtz kuruk kutob kuttu kutur kuzbu o-r-b oboro obout obrok obzor okbut okkur okobo okoro okrut okubo okuku okuru ooooo orbot orkut orobo orout ortok ortoo oruku oruro orutu otoku ototo otour otrok ottur oubut ouoro outro outto ozoro ro-ro robbo robo- robor robot robrt robur rokkk rokot rokto rorbu rotko roto- rotor rotot rotto rotz rotzo roubt rouko routt rt-rk rubor ruutu tbtbt tbutt tobor tobot tobou tokko toko- tokor tokuo tokur torob torok torro torto tortu toto- totok totoo touro trbuk trooz trott trout trubu truro ttttt tubo- tubou tukur tuotu turbo turbt turko turku turok turot turro turtu turut tutku tutor tutto tuuru ubobo ukobu urkut uroob urour urroz urubu urutu urzut utro- utror uttur uturu ututo utzoo uuork uuuuu z-out zokor zorbo zorko zorro zotob zotto zrbtt zu-zu zubko zubuk zukor zzzzz