a-ak a-ok aaaa aaab aaap aaar aaba aabb aabp aaka aaoo aapa aapo aara aaro aarp abaa abab abak abap abar abb- abba abbb abbo abbr aboa abob abok aboo abor abpa abpp abpr abra abro akaa akao akap akar akka akko akok akpo akr- akra aoba aokp aopo aora aorb apak apao apap apar apba apbr apo- apoo apop apor appa appr apra apro arab arak arap arar arba arka arko aroa arob aroo aror arpa arr- arra arrk arro arrr baaa baak baar baba babb babo babr bak- baka bako bakr bapa bapp bar- bara barb bark baro barr bbbb bbpr bkpr boab boak boar boba bobb bobo boka boko boob book boop boor bopa bopp bor- bora bork boro borr brab brak brao brka brkb broa brob brok broo bror brrr kaaa kaab kaak kaap kaar kaba kabb kabo kabr kaka kakk kako kaoa kaok kaor kap- kapa kapo kapp kara karb kark karo karp karr kbaa kbab kbak kbap kbar kbba kbbb kbbk kbbo kbbr kbkb kbkk kbko kbkr kboa kbob kbok kboo kbpa kbpk kbpo kbpr kbra kbrb kbrk kbro kkaa kkap kkar kkba kkbb kkbo kkbr kkkk kkoa kkob kkoo kkor kkpk kkrb kkrk kkro kkrr koab koak koap koar koba kobb kobk kobo kobr koka kokb kokk koko kokp kokr koob kook kooo koop koor kopa kopb kopp kopr kora korb kork koro korr kpak kpao kpar kpba kpbb kpbr kpkk kpkr kpoa kpob kpok kpoo kpop kppk kppo kppp kppr kprb kprk kpro kprp kprr krab krak krap krar krba krbb krbk krbr krka krkk krko krkr kroa krob krok kroo krop kror krpa krpr krrb krrk krro krrr oara obak obba obbo obkb obok obor obra obro okak okap okka okko okok okor okpo okra okro ooaa ooak ooba oooo oora opap opar opo- opor oppa oppo opra orab orak orao orar orba orbb orbo orka orko oro- orok oror orra orro paak paap paar paba paka pako papa papb papp papr par- para park paro parp parr pbar pbpa pbpk poak poar poba pobo poka poko pook poop poor pop- popa popo popp pora porb pork poro porr ppap ppar ppoa pppa pppo pppp prao prar pro- proa prob proo prop raab raak raba rabb rabk rabo raka rakk raob raok raop rapa rapp rara rarb rark raro rbbb rbbr roab roak roap roar rob- roba robb robo roka rokk roko rokr roob rook roop roor ropa ropo rora rork roro rpob rrrr