-er b-u bbb bbc bbe bbk bbo bbr bbu bcb bcc bce bck bco bcr bcu be- beb bec bee bek beo ber beu bkb bkc bke bkk bko bkr bob boc boe bok boo bor bou brb bre brk bro brr bru bub buc bue buk buo bur buu c-- cbb cbc cbe cbk cbo cbr cbu ccb ccc cce cck cco ccr ccu ce- ceb cec cee cek ceo cer ceu ckb ckc cko co- cob coc coe cok coo cor cou crb crc cre crk cro crr cru cub cuc cue cuk cuo cur cuu ebb ebc ebe ebk ebo ebr ebu ec- ecb ecc ece eck eco ecr ecu eeb eec eee eek eeo eer ekb ekc eke eko ekr eku eo- eob eoc eoe eok eoo eor eou erb erc ere erk ero err eru eu- eub euc eue eur kbb kbc kbe kbk kbo kbr kbu kcb kcc kce kck kcr kcu ke- keb kec kee kek keo ker kkb kkc kke kkk kkr kku kob koc koe kok koo kor kou krc krk kro krr kru kub kuc kue kuk kur kuu ob- obb obc obe obk obo obr obu oc- ocb occ ock oco ocr ocu oeb oec oee oeo oer okb okc oke okk oko okr oku oo- oob ooc ook ooo oor or- orb orc ore ork oro orr oru ou- ouc oue ouk ouo our rbb rbc rbe rbk rbo rbr rbu rcb rcc rce rco rcr rcu re- reb rec ree rek reo rer reu rkb rkc rke rkk rko rku rob roc roe rok roo ror rou rrb rrc rrk rrr rru rub ruc rue ruk ruo rur ruu ubb ubc ube ubk ubo ubr ubu ucb ucc uce uck uco ucr ucu ueb uec uee uer ukb ukc uke ukk ukr uku uob uoc uoe uok uoo uor ur- urb urc ure urk uro urr uru uuc uue uur uuu

bbbb bbeb bbrc bcbc bccc bcec bcer bcor bcru bcuc bebb bebe bebo beck becu beeb beek beer beke beko beo- beok beor berc bere berk bero berr beru beuk beur bobb bobe bobo bobu boce bock boco bocu boec boee boeo boer boke boko boku boob booc booe book boor bor- bore bork boro borr boru boue bouk bour brcb brce breb brec bree brek breo brer brkb brob broc broe brok broo bror brou brrr bruc brue bubb bube bubo bubu bucc buce buck buco bucu buer bueu buke bukk buko buku bur- burb bure burk buro burr buru c-bo cbbc cbcc cbce cbcr cbcu cbec cbee cber cbko cbkr cbre ccbc cccb cccc cccu ccee ccob ccoc ccrc ccre ccuc cebu cec- cece ceco ceeb ceec ceke ceor ceou cer- cerc cere cero ckbc ckbe ckck ckco cker ckob ckoc ckoo ckor ckrc cobb cobe cobo cobu coce cock coco cocu cok- coke coko coob cook cor- corb corc core cork coro corr coub coue couk cour crbc crbu crcc crce crcr cre- creb crec cree creo creu crkc crob croc croe crok croo cror crub crue cruk cub- cubb cube cucc cuce cuck cuek cuer cuk- cuke curb cure curo curr ebbc ebbo ebbr ebcc eber eboe eboo ebor ebro ebru ebur ecbc ecbe eccb eccc ecce ecco ecko eco- ecou ecrc ecrr ecru eeee eeke eeoc eerc eero ekco ekeb ekek eker ekur eore erbb erbe ercc erce ereb erec erer erke erob eroc eroe eroo errc erre erro erub eruc erur eubc euer eur- eurc eure euro kbbb kbbc kbbe kbbk kbbo kbbr kbbu kbcb kbce kbck kbco kbcr kbcu kbeb kbec kbee kbek kbeo kber kbkb kbkk kbko kbkr kbob kboc kboe kbok kboo kbrb kbrc kbre kbrk kbro kbru kbub kbuc kbue kbuk kbur kbuu kcbc kcbk kcbr kcbu kccb kccc kcck kccr kccu kceb kcec kcee kceo kceu kckc kckk kcko kckr kcob kcoe kcor kcou kcrc kcro kcrr kcru kcub kcue kcuk kebb kebc kebe kebr kebu keck keco kecr keek keer kekb kekc keke keko keku keok ker- kerb kerc kere kerk kero kerr keru keur kkbb kkbe kkbo kkbr kkcb kkck kkco kkcr kkkk kkob kkoo kkor kkrb kkrc kkre kkrk kkro kkrr kkuu kobb kobc kobe kobk kobo kobr kobu kocb kock kokb kokc koke kokk koko kokr koku koob kooc kook kooo koor koou korb korc kore kork koro korr koru koub koue kour kouu krbb krbe krbk krbr krcb krcc krce krco krcu kreb krec kree krek kreo kreu krkc krke krkk krko krkr krku krob kroc kroe krok kroo kror krrb krrc krre krrk krro krrr kruc krue kruk krur kubb kubc kube kubo kubr kubu kucb kucc kuce kuco kucr kuek kueu kuke kukk kuku kuok kuoo kurb kure kurk kuro kurr kuru kuub kuuk kuur kuuu o-eo obbo obec ober obkb oboe obok obor obre obro ocbc occc oce ocee ocke ocre ocro ocrr ocur oec- oecc oeec oere okcu oker okko okok okor okre okro okur oobe oocr ooer ooku oooo oore orbb orbe orbo orbu orce orco ore- oreb orec orek oreo orer orke orko oro- oroe orok oror orro orub oucc ouer our- oure ouro ouu- rbbb rbbr rcbc rcbo rccb rccc rebb rebe rebk rebo rebu recc rece reck recr recu reeb reek reke reko reou rere rero reru reue reuk reuu rob- robb robe robo robu rocc roce rock roco roer roke rokk roko rokr roku roob rook roor rorc rore rork roro roru roub roue rouk rrrr rubb rube rubu ruce ruck ruer ruke rukk ruku ruok rurc rure ruro ruru ubbe ubbo ubek uber uboc ucbc ucrc ukcc ukek ukeu ukko ukok ukrc ukur uocc uoke uor- uore urbe ure- urke uro- urok uroo urre uruk urur uuoc uuuu

b-r-k bbbee bbook bcock be-er be-ro bebek beber becco becke becue beebe beeke beker bekke bekko bekok beour berbe berck bercu berec berek berk- berke berko berob beroe berok beror berre berru beuer beure bo-bo bobek bobko boboc bobok bobr bobre bocce