b-u bbb bbd bbi bbk bbo bbr bbu bdb bdd bdi bdk bdo bdr bdu bi- bib bid bii bik bio bir biu bkb bkk bko bkr bob bod boi bok boo bor bou brb brd bri brk bro brr bru bub bud bui buk buo bur buu dbb dbd dbi dbk dbo dbr dbu ddb ddd ddi ddk ddo ddr ddu di- dib did dii dik dio dir diu dkb dki dkk dko dkr dku dob dod doi dok doo dor dou drb drd dri drk dro drr dru dub dud dui duk duo dur i-d ibb ibd ibi ibk ibo ibr ibu idb idd idi idk ido idr idu iib iid iii iio iir iiu ikb iki ikk iko ikr iku io- iob iod ioi ioo ior iou ir- irb ird iri irk iro irr iru iu- iub iud iui iur kbb kbd kbi kbk kbo kbr kbu kdb kdk kdo kdr kdu kib kid kii kik kio kir kiu kkb kki kkk kkr kku kob kod koi kok koo kor kou krd kri krk kro krr kru kub kud kui kuk kur kuu o-i ob- obb obd obi obk obo obr obu odb odd odi odo odr odu oib oid oii oik oio oir oiu okb okd oki okk oko okr oku oo- oob ood ooi ook ooo oor or- orb ord ori ork oro orr oru ou- oud oui ouk ouo our rbb rbd rbi rbk rbo rbr rbu rdb rdd rdi rdo rdr rdu rib rid rii rik rio rir rkb rkk rko rku rob rod roi rok roo ror rou rrb rrd rri rrk rrr rru rub rud rui ruk ruo rur ruu ubb ubi ubk ubo ubr ubu udb udd udi udk udo udr udu uib uid uii uio uir uiu ukb uki ukk ukr uku uob uod uok uoo uor ur- urb urd uri urk uro urr uru uur uuu