b-r-k bbook bhook bhoom bhour bo-bo bo-ho bobko bobok bobr bohok bohor bokko bokok bokor bombo bomoh booko boomb booru borbo borko borku bormo boro- borok borom boroo borou borro borum bouko brmmm brobo brohm brom- bromo brook broom brouk brrrr brumm bukk- bukom bukor bumbo bumbu buoho buroo burro burru buruk hbomb hhhhh hhour hkhrm ho-ho ho-oh hobor hobro hobub hohum hokku hokum homo- homok horom horro horru hubur huhuh hukok humbo humor humur huork hurko hurm hurok hurum huuru k-rob khoku khoro khoum khour khumb khuru khuur ko-ko kobru kobuk kohmo kokko kokor kokou kokum kokur kombo kombu komku kooru korbo korku korom koror korro koruk kromo krumm kubok kuhmo kukko kukok kukur kumbh kumbo kumru kumuk kurbu kurku kuruk mboro mburu mhorr mmhmm mmmmm mobor mobro mohor mohur mokko mokro mokuk mokum mombo mombu mookk mooro morbo mormo moror morou morro morum mrmom mrorr mukho mukur mumbo mummu mumok murko murom muror murrh murro murru muruk murum o-hum o-r-b obhor oboro obrok obrom oh-oh oh-ok ohmmm ohour ohrob ohrum okkur okobo okoho okoro okubo okuku okuru omoro omuku ooooh ooooo orbom orkom ormur orobo oromo orrum oruku oruro ouoro rhomb rhumb ro-ro robbo robo- robor robur rohob rohru rokkk rookh roomu rorbu rouko roumm rubor ruhub rumbo rummo rummu rumor ruomu ubobo uh-oh uh-uh uhhoh uhhuh uhuru ukobu umbro umhum umour uroob urour urubu uuork uuuuu