bbbb bbeb bbet bbpr bebb bebe bebi beeb beep beer beet beir beit bere beri berr bert beru bete beti bett betu beur bibb bibe bibi bieb bier biet bieu bipp bipu birb bire biri birr birt biru bite bitt bitu bpti breb bree brei brep brer bret brie brit brrr brue brup brut btbp btie btrt bttb bubb bube bubi bubu buer bueu buie buir buit buiu bur- burb bure buri burp burr burt buru but- bute buti butt ebbr eber ebit ebru ebur eeee eete eetu eiei eier eipr eire eitb eiti eitr epee eper epi- epie epip epit eppp eprb eprp epte epub erbb erbe ereb erei erer eret erie erit eriu erpe erre ertu erub erur etbr etee eter etre ette etti ettu etui eubi euer eur- eure eurt i-be ibet ibie ibri ibtb ieet ieie iere ieri iett iiie iiii iiit iitr iitt iper ipet ipie ippr ipri ipur iput irbe irbp iree irer iri- irie irip irpe irre irri irte irti irtp itbe itep iter itet itie itri itup itur iuiu iupp peep peer peet peip peir peit pepe pepi per- pere peri perp perr pert peru pete peti petr pett peur peut pibb pibi piep pier piet piip pipe pipi pipp pire piri pirr piru pite piti pitr pitt pitu pper ppib ppie pppp ppru pptt ppur pre- preb pree prep pret preu pri- prie prii prri prti prtp prtr prue prut pruu pter ptui pu-e pube pubu puer puet pueu puir puit puiu pupe pupi pupu pur- purb pure puri purp purr puru put- pute puti putt putu rbbb rbbr rebb rebe rebu reeb reep reet reii reir reit reiu repe repi repp repr rept repu rere reri rert reru rete reti retr rett reue reup reut reuu rib- ribe ribu riep rier riet rieu ripe ripi ripp ripr ript rire riri rite riti ritt ritu riue rpet rpii rrrr rtee rtei rttp rubb rube rubi rubp rubu ruer ruet ruit rupe rupp rupt rure ruri rurp ruru rute ruti rutt rutu tbit tbrb tbtp tebu teer teet teie teip teir teiu tepe tepi tepp tepu ter- tere teri terp terr teru tete teti tetr tett tetu teut tibi tibu tie- tiee tiei tiep tier tiet tiit tiiu tip- tipe tipi tipp tipt tipu tirb tire tiri tirr tiru tite titi titp titt titu tper tpir tppp tppr tpte tptp tptr tput tre- tree trei tret treu tri- trib trie trip trit trpe trpp trte trtr trub true trut truu ttbb tter tttt tubb tube tubr tubu tuei tuer tuet tuit tuiu tupe tupi tupu turb ture turi turp turr turt turu tute tuti tutt tutu u-ie u-rp ubbe ubbi uber ubet ubii ubir ubit ueir uepi uipi uirr upbe upie uppe uppp uppu upri upup urbe urbi ure- uret urib urie uriu urre urri urte urup urur urut utep uter utri utti uttu uuri uuuu