a-ak a-be a-ok aaaa aaab aaac aaae aaar aaba aabb aabc aaca aacb aacc aace aack aaco aacr aaea aaec aaka aake aaoe aaoo aara aarc aare aaro abaa abab abac abae abak abar abb- abba abbb abbe abbo abbr abca abcb abcc abcr abec abee aber aboa abob abok aboo abor abra abrc abro acaa acab acac acae acar acba acca accc acce acco ace- acea acec acek acer acke acoa acoe acor acr- acra acrc acre acro acrr aeac aecb aeer aeka aer- aera aerc aero akaa akae akao akar akca akee aker akka akko akok akr- akra akre aoba aoca aoce aora aorb arab arac arae arak arar arba arbe arc- arca arce arco area arec aree arek areo arka arke arko aroa arob aroe aroo aror arr- arra arrc arre arrk arro arrr baaa baak baar baba babb babe babo babr bac- baca bacc bace back baco baek baer bak- baka bake bako bakr bar- bara barb barc bare bark baro barr bbbb bbeb bbrc bcaa bcar bcbc bcca bccc bcec bcer bcor bcra beak bear beba bebb bebe bebo beca beck beeb beek beer beka beke beko beo- beok beor bera berc bere berk bero berr boab boac boak boar boba bobb bobe bobo boca boce bock boco boea boec boee boeo boer boka boke boko boob booc booe book boor bor- bora bore bork boro borr brab brac brae brak brao brca brcb brce brea breb brec bree brek breo brer brka brkb broa brob broc broe brok broo bror brrr c-bo caaa caab caac caba cabe cabo cac- caca cacc cace cack caco cacr caec caer caka cake caor cara carb carc care cark caro carr cbac cbar cbbc cbca cbcc cbce cbcr cbea cbec cbee cber cbka cbko cbkr cbre ccaa ccab ccac ccar ccba ccbc ccca cccb cccc ccee ccob ccoc ccra ccrc ccre ceac cear ceba cec- ceca cece ceco ceeb ceec ceke ceor cer- cera cerc cere cero ckac ckbc ckbe ckck ckco cker ckoa ckob ckoc ckoo ckor ckrc coak coba cobb cobe cobo coca coce cock coco cok- coka coke coko coob cook cor- cora corb corc core cork coro corr crab crac crar crbc crca crcc crce crcr cre- crea creb crec cree creo crkc crob croc croe crok croo cror eaba eaca eacc eaec eara earb eare earo ebac ebba ebbc ebbo ebbr ebcc eber eboe eboo ebor ebro ecaa ecac ecao ecar ecbc ecbe ecca eccb eccc ecce ecco ecka ecko eco- ecra ecrc ecrr eeca eeea eeee eeka eeke eeoc eera eerc eero eka- ekab ekco ekeb ekek eker ekka ekoa eoka eora eore erba erbb erbe erca ercc erce ereb erec erer erke erob eroc eroe eroo erra errc erre erro kaaa kaab kaak kaar kaba kabb kabc kabe kabo kabr kacb kacc kace kaco kaeo kaer kaka kakc kake kakk kako kaoa kaoc kaok kaor kara karb kare kark karo karr kbaa kbab kbac kbae kbak kbar kbba kbbb kbbc kbbe kbbk kbbo kbbr kbca kbcb kbce kbck kbco kbcr kbeb kbec kbee kbek kbeo kber kbkb kbkk kbko kbkr kboa kbob kboc kboe kbok kboo kbra kbrb kbrc kbre kbrk kbro kcaa kcab kcac kcar kcba kcbc kcbk kcbr kcca kccb kccc kcck kccr kcea kceb kcec kcee kceo kckc kckk kcko kckr kcob kcoe kcor kcrc kcro kcrr kea- keak kear keba kebb kebc kebe kebr keca keck keco kecr keek keer keka kekb kekc keke keko keok ker- kera kerb kerc kere kerk kero kerr kkaa kkac kkar kkba kkbb kkbe kkbo kkbr kkcb kkck kkco kkcr kkea kkkk kkoa kkob kkoo kkor kkrb kkrc kkre kkrk kkro kkrr koab koac koae koak koar koba kobb kobc kobe kobk kobo kobr koca kocb kock koea koka kokb kokc koke kokk koko kokr koob kooc kook kooo koor kora korb korc kore kork koro korr krab krac krae krak krar krba krbb krbe krbk krbr krca krcb krcc krce krco krea kreb krec kree krek kreo krka krkc krke krkk krko krkr kroa krob kroc kroe krok kroo kror krrb krrc krre krrk krro krrr o-eo oaer oake oara oare obak obba obbo obea obec ober obkb oboe obok obor obra obre obro ocab ocac ocak ocbc occa occc oce ocee ocke ocra ocre ocro ocrr oec- oeca oecc oeec oera oere okak oker okka okko okok okor okra okre okro ooaa ooak ooba oobe oocr ooer oooo oora oore orab orac orae orak orao orar orba orbb orbe orbo orca orce orco ore- orea oreb orec orek oreo orer orka orke orko oro- oroe orok oror orra orro raab raak raba rabb rabe rabk rabo rac- raca racc race rack raco raec raer raka rake rakk raob raoc raok rara rarb rare rark raro rbbb rbbr rcac rcbc rcbo rccb rccc rea- reac reae reak reao rear reba rebb rebe rebk rebo reca recc rece reck recr reeb reek reka reke reko rera rere rero roab roak roar rob- roba robb robe robo roca rocc roce rock roco roea roer roka roke rokk roko rokr roob rook roor rora rorc rore rork roro rrrr