a-be aaaa aaab aaae aaap aaar aaba aabb aabp aaea aaep aaoe aaoo aapa aapo aara aare aaro aarp abaa abab abae abap abar abb- abba abbb abbe abbo abbr abee aber aboa abob aboo abor abpa abpp abpr abra abro aeap aeer aer- aera aero aoba aopo aora aorb apao apap apar apba apbr apea apep aper apo- apoe apoo apop apor appa appr apra apre apro arab arae arap arar arba arbe area aree areo arep aroa arob aroe aroo aror arpa arpe arr- arra arre arro arrr baaa baar baba babb babe babo babr baer bapa bape bapp bar- bara barb bare baro barr bbbb bbeb bbpr beap bear beba bebb bebe bebo beeb beep beer beo- beor bepo bera bere bero berr boab boar boba bobb bobe bobo boea boee boeo boep boer boob booe boop boor bopa bope bopp bor- bora bore boro borr bpea bpoe brab brae brao brea breb bree breo brep brer broa brob broe broo bror brrr eaba eaop eapp eara earb eare earo earp ebba ebbo ebbr eber eboe eboo ebor ebpo ebro eeea eeee eera eero eora eore epaa epee eper epor eppa eppo eppp epra eprb epro eprp erap erba erbb erbe ereb erer erob eroe eroo erpa erpe erra erre erro o-eo oaer oara oare obba obbo obea ober oboe obor obra obre obro oepa oera oere ooaa ooba oobe ooer oooo oora oore opap opar opep oper opo- opor oppa oppo opra orab orae orao orar orba orbb orbe orbo ore- orea oreb oreo orer oro- oroe oror orpe orra orro paap paar paba paea paep paer papa papb pape papp papr par- para pare paro parp parr pbar pbpa peab peap pear peba peep peer peor pepa pepe pepo per- pera pere pero perp perr poar poba pobo poea poer poop poor pop- popa pope popo popp pora porb pore poro porr ppap ppar pper ppoa pppa pppo pppp prae prao prar pre- preb pree prep pro- proa prob proe proo prop raab raba rabb rabe rabo raep raer raob raop rapa rape rapp rara rarb rare raro rbbb rbbr rea- reae reao reap rear reba rebb rebe rebo reeb reep reop repe repo repp repr rera rere rero roab roap roar rob- roba robb robe robo roea roer roob roop roor ropa rope ropo rora rore roro rpob rpoe rrrr