bbbb bbeb bbpr bebb bebe beeb beek beep beer beke bere berk berr beru beuk beur bkpr breb bree brek brep brer brkb brrr brue brup bubb bube bubu buer bueu buke bukk buku bur- burb bure burk burp burr buru ebbr eber ebru ebur eeee eeke ekeb ekek eker ekpe ekur epee eper eppp eprb eprp epub erbb erbe ereb erer erke erpe erre erub erur euer eur- eure kbbb kbbe kbbk kbbr kbbu kbeb kbee kbek kber kbkb kbkk kbkr kbpe kbpk kbpr kbpu kbrb kbre kbrk kbru kbub kbue kbuk kbup kbur kbuu kebb kebe kebr kebu keek keep keer kekb keke keku kep- kepe kepu ker- kerb kere kerk kerp kerr keru keup keur kkbb kkbe kkbr kkkk kkpk kkrb kkre kkrk kkrr kkup kkuu kpbb kpbe kpbr kpek kper kpke kpkk kpkr kppk kppp kppr kprb kpre kprk kprp kprr kpru kpub kpur krbb krbe krbk krbr kreb kree krek kreu krke krkk krkr krku krpr krpu krrb krre krrk krrr krue kruk krup krur kubb kube kubr kubu kuek kueu kuke kukk kuku kupb kupe kupr kupu kurb kure kurk kurr kuru kuub kuuk kuur kuuu pbpk peek peep peer peke pekk pepe per- pere perk perp perr peru peur pper pppp ppru ppur pre- preb pree prek prep preu prue pruu pu-e pube pubu puer pueu puke puku pupe pupu pur- purb pure purp purr puru rbbb rbbr rebb rebe rebk rebu reeb reek reep reke repe repp repr repu rere reru reue reuk reup reuu rrrr rubb rube rubp rubu ruer ruke rukk ruku rupe rupp rure rurp ruru u-rp ubbe ubek uber ukek ukeu ukup ukur upbe uppe uppp uppu upup urbe ure- urke urre uruk urup urur uuuu