b-r-k bbook bo-bo bobko bobok bobr bokko bokok bokor booko booru borbo borko borku boro- borok boroo borou borro bouko brobo brook brouk brrrr bukk- bukor buroo burro burru buruk k-rob ko-ko kobru kobuk kokko kokor kokou kokur kooru korbo korku koror korro koruk kubok kukko kukok kukur kurbu kurku kuruk o-r-b oboro obrok okkur okobo okoro okubo okuku okuru ooooo orobo oruku oruro ouoro ro-ro robbo robo- robor robur rokkk rorbu rouko rubor ubobo ukobu uroob urour urubu uuork uuuuu