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 abax abb- abba abbb abbe abbo abbr abee aber aboa abob aboo abor abox abpa abpp abpr abra abro aeap aeer aer- aera aero aoba aopo aora aorb apao apap apar apax apba apbr apea apep aper apex apo- apoe apoo apop apor apox appa appr appx apra apre apro arab arae arap arar arax arba arbe area aree areo arep arex aroa arob aroe aroo aror arpa arpe arr- arra arre arro arrr axar axer axo- axoa axxo ba-x baaa baar baba babb babe babo babr baer bapa bape bapp bar- bara barb bare baro barr barx bbbb bbeb bbox 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 boox bopa bope bopp bor- bora bore boro borr boxa bpea bpoe brab brae brao brax brea breb bree breo brep brer brex broa brob broe broo bror brox brrr eaba eaop eapp eara earb eare earo earp ebba ebbo ebbr eber eboe eboo ebor ebox ebpo ebro eeea eeee eera eero eora eore epaa epee eper epor epox eppa eppo eppp epra eprb epro eprp epxp er-x erap erba erbb erbe ereb erer erob eroe eroo erpa erpe erra erre erro exa- exer exo- exor expo expr exrx o-eo oaer oara oare obba obbo obea ober obex oboe obor obox obra obre obro oeax oepa oera oere ooaa ooba oobe ooer oooo oora oore opap opar opep oper opex opo- opor oppa oppo opra orab orae orao orar orba orbb orbe orbo ore- orea oreb oreo orer orex oro- oroe oror orpe orra orro oxa- oxea oxep oxer oxo- oxox oxxo paap paar paba pabx paea paep paer paox papa papb pape papp papr par- para pare paro parp parr paxo pbar pbpa peab peap pear peax 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 prex pro- proa prob proe proo prop prox raab raba rabb rabe rabo raep raer raob raop rapa rape rapp rara rarb rare raro raxa rbbb rbbr rea- reae reao reap rear reba rebb rebe rebo reeb reep reop repe repo repp repr rera rere rero rexx roab roap roar rob- roba robb robe robo roea roer roob roop roor roox ropa rope ropo rora rore roro roxa roxo rpob rpoe rrrr xaar xapo xara xare xbar xbee xbox xbra xeer xer- xera xero xexe xoro xorp xoxo xpax xper xpra xrep xxxo xxxx