b-u bbb bbi bbk bbr bbu bi- bib bii bik bir biu bkb bkk bkr brb bri brk brr bru bub bui buk bur buu ibb ibi ibk ibr ibu iib iii iir iiu ikb iki ikk ikr iku ir- irb iri irk irr iru iu- iub iui iur kbb kbi kbk kbr kbu kib kii kik kir kiu kkb kki kkk kkr kku kri krk krr kru kub kui kuk kur kuu rbb rbi rbk rbr rbu rib rii rik rir rkb rkk rku rrb rri rrk rrr rru rub rui ruk rur ruu ubb ubi ubk ubr ubu uib uii uir uiu ukb uki ukk ukr uku ur- urb uri urk urr uru uur uuu