a-ak a-do a-ok aaaa aaab aaac aaad aaaf aaar aaba aabb aabc aabd aaca aacb aacc aacd aacf aack aaco aacr aada aadc aafa aafb aafc aafd aaff aaka aaoo aara aarc aard aaro abaa abab abac abad abaf abak abar abb- abba abbb abbo abbr abca abcb abcc abcd abcf abcr abda abdo abff aboa abob abod abof abok aboo abor abra abrc abro acaa acab acac acad acar acba acca accc accd accf acco acda acdb acdc acdf acfc acfd ackd acoa acod acor acr- acra acrc acro acrr adaa adab adac adad adak adao adar adba adbc adcc adda addc addd addo addr adfa adfc adob adoc adod adok adoo ador adra adro afaa afad afak afao afar afca afcb afcc afdb afdc affa affc affo afka afkr afoa afoo afor afr- afra afrc afro akaa akao akar akca akka akko akok akr- akra aoba aoca aora aorb arab arac arad araf arak arar arba arc- arca arco arda ardc ardf ardo arfa arfb arfc arff arka arko aroa arob arod aroo aror arr- arra arrc arrk arro arrr baaa baad baaf baak baar baba babb babo babr bac- baca bacc back baco bada badb badd bado badr bafc baff bafo bak- baka bako bakr bar- bara barb barc bard barf bark baro barr bbad bbbb bbdd bbdo bbfc bbrc bcaa bcar bcbc bcca bccc bcda bcfc bcof bcor bcra bd-r bdbc bddc bfca boab boac boad boak boar boba bobb bobo boca bock boco boda bodb bodo bofa bofd boff boka boko boob booc bood boof book boor bor- bora bord borf bork boro borr brab brac brad braf brak brao brca brcb brda brdo brfc brka brkb broa brob broc brod brok broo bror brrr c-bo c-cd caaa caab caac caaf caba cabf cabo cac- caca cacc cack caco cacr cada cadc cadd cado cadr cafa cafb cafc caff caka caod caor cara carb carc card carf cark caro carr cbac cbar cbbc cbca cbcc cbcr cbdb cbdc cbdo cbfb cbfc cbka cbko cbkr cbrd ccaa ccab ccac ccad ccaf ccar ccba ccbc ccca cccb cccc cccf ccdc ccdf ccdr ccfa ccfc ccfd ccff ccob ccoc ccod ccra ccrc ccrf cd-r cdaa cdac cdad cdba cdbf cdda cddb cddr cdfa cfaa cfab cfac cfao cfar cfbc cfbr cfca cfcb cfcf cfco cfda cffb cffr cfoa cfor cfra cfrb ckac ckbc ckck ckco ckdo ckfr ckoa ckob ckoc ckoo ckor ckrc ckrd coad coak coba cobb cobo coca cock coco coda codd cofc coff cok- coka coko coob cood coof cook cor- cora corb corc cord corf cork coro corr crab crac craf crar crbc crca crcc crcr crda crdc crfc crkc crob croc crod crok croo cror d-bo daab daad daar daba dabb dabo daca dada dado dafa dafc daff dafo daka dako dara darb darc dard darf dark daro darr dbar dbcc dbfc dbfo dcbc dcca dccb dccc dcdb dcfc dcra dcrk dddd ddoc ddrc dfaf dfcc dfco dffa dfrf dkba dkdc doab doak doar doba dobb doca dock doco dod- doda dodd dodo doff doka doko doob dood doof dook door dora dorc dord dorf dork doro dorr draa drab drac drad draf drak drar drba drbc drca drda drfc drob drod drof drra f--k faaa faac faad faba fabd fabo faca facc fack fada fadd fado fafa fafc faff fafo fako fara farb farc fard fark faro farr fbar fcab fcar fcba fcca fccf fcda fcra fdca fdoa fdoc ffar ffcc ffff ffrr fkab foad foaf foak foar foba foca fock foco foda fofo food foof fook for- fora forb ford fork foro forr frab frac frad frak frbc frcc frfc frob kaaa kaab kaaf kaak kaar kaba kabb kabc kabd kabf kabo kabr kacb kacc kacd kaco kad- kada kadd kadf kado kadr kafa kafc kaff kafr kaka kakc kakk kako kaoa kaoc kaok kaor kara karb kard karf kark karo karr kbaa kbab kbac kbad kbak kbar kbba kbbb kbbc kbbd kbbf kbbk kbbo kbbr kbca kbcb kbck kbco kbcr kbdb kbdf kbdo kbdr kbfb kbfc kbff kbfk kbfo kbfr kbkb kbkf kbkk kbko kbkr kboa kbob kboc kbod kbok kboo kbra kbrb kbrc kbrd kbrf kbrk kbro kcaa kcab kcac kcad kcar kcba kcbc kcbd kcbf kcbk kcbr kcca kccb kccc kccd kcck kccr kcda kcdc kcdd kcdr kcfa kcfb kcfc kcfd kcfo kckc kckf kckk kcko kckr kcob kcof kcor kcrc kcro kcrr kdaa kdab kdac kdad kdaf kdak kdao kdar kdbb kdbr kdca kdcc kdcd kdco kdcr kddb kddc kddd kddf kddk kddr kdfc kdfo kdfr kdka kdkb kdkd kdkk kdko kdkr kdoc kdok kdrb kdrf kdro kfab kfac kfar kfbc kfbk kfcd kfcf kfco kfcr kfda kffa kffb kfff kffk kfka kfkb kfok kfoo kfor kfra kfrc kfrd kfro kfrr kkaa kkac kkar kkba kkbb kkbd kkbo kkbr kkcb kkcd kkck kkco kkcr kkda kkdc kkdd kkdo kkfr kkkk kkoa kkob kkoo kkor kkrb kkrc kkrf kkrk kkro kkrr koab koac koak koar koba kobb kobc kobk kobo kobr koca kocb kocd kocf kock koda kodk kodo kofa kofc koff kofk kofo koka kokb kokc kokf kokk koko kokr koob kooc kook kooo koor kora korb korc kord korf kork koro korr krab krac krad krak krar krba krbb krbd krbk krbr krca krcb krcc krcd krco krda krdc krdd krdo krdr krfc krfd krff krfo krka krkc krkd krkk krko krkr kroa krob kroc krod krof krok kroo kror krrb krrc krrf krrk krro krrr oafc oafo oara obad obak obba obbo obkb obok obor obra obro ocab ocac ocad ocak ocbc occa occc ocfa ocra ocro ocrr odac odbo odda oddd odoo odor odra ofcr ofdr off- offa offc offo offr ofor ofra okak okka okko okok okor okra okro ooaa ooak ooba oocr ooda ooff oooo oora oord orab orac orad orak orao orar orba orbb orbo orca orco orda ordo orff orka orko oro- orof orok oror orra orro raab raad raaf raak raba rabb rabk rabo rac- raca racc rack raco