a-be aaaa aaab aaae aaap aaar aaba aabb aabp aabt aaea aaep aapa aapt aara aare aarp aart aata aatt abaa abab abae abap abar abat abb- abba abbb abbe abbr abbt abee aber abet abpa abpp abpr abra abta aeap aeer aer- aera aeta aetr aett apap apar apat apba apbr apea apep aper apet appa appr appt apra apre aprt apta apte aptt arab arae arap arar arat arba arbe area aree arep aret arpa arpe arr- arra arre arrr arrt arta arte artr at-t ataa atab atae atap atar atat atea atee atep ater atpr atra atre atrp atta atte attp attr baaa baar baat baba babb babe babr baer bapa bape bapp bapt bar- bara barb bare barr bart bata bate batt bbbb bbeb bbet bbpr beap bear beat beba bebb bebe beeb beep beer beet bera bere berr bert beta bete bett bpea brab brae brat brea breb bree brep brer bret brrr btaa btbp btrt bttb eaba eapp eara earb eare earp eart eata eate ebba ebbr eber eeea eeee eera eeta eete epaa epee eper eppa eppp epra eprb eprp epta epte erap erat erba erbb erbe ereb erer eret erpa erpe erra erre erta etap etat etbr etee eter etra etre etta ette paap paar paat paba pabt paea paep paer papa papb pape papp papr par- para pare parp parr part pata pate patr patt pbar pbpa peab peap pear peat peba peep peer peet pepa pepe per- pera pere perp perr pert peta pete petr pett ppap ppar pper pppa pppp ppta pptt prae prar prat pre- preb pree prep pret prtp prtr ptab pter raab raat raba rabb rabe raep raer rapa rape rapp rapt rara rarb rare rata rate ratp ratt rbbb rbbr rea- reae reap rear reat reba rebb rebe reeb reep reet repe repp repr rept rera rere rert reta rete retr rett rpet rpta rrat rrrr rtee rtpa rttp taa- taar taat taba tabb tabe taer tapa tape tapp tapr tapt tara tarb tare tarp tarr tart tata tatb tate tatr tatt tbar tbrb tbta tbtp tear teat teba teer teet tepa tepe tepp ter- tera tere terp terr teta tete tetr tett tpap tper tppa tppp tppr tpte tptp tptr traa trab trae trap trat tre- trea tree tret trpa trpe trpp trra trte trtr ttab ttbb tter tttt