a-be aaaa aaab aaae aaaf aaar aaba aabb aabt aaea aafa aafb aaff aara aare aart aata aatf aatt abaa abab abae abaf abar abat abb- abba abbb abbe abbr abbt abee aber abet abff abra abta aeaf aeer aer- aera aeta aetf aetr aett afaa afar afat afee afer afet affa afft afr- afra afre afta afte arab arae araf arar arat arba arbe area aree aref aret arfa arfb arff arft arr- arra arre arrr arrt arta arte artr at-t ataa atab atae atar atat atea atee atef ater atfb atfe atra atre atta atte attr baaa baaf baar baat baba babb babe babr baer baff baft bar- bara barb bare barf barr bart bata bate batf batt bbbb bbeb bbet beaf bear beat beba bebb bebe beeb beef beer beet befa befe beff beft bera bere berr bert beta bete bett bfta bftt brab brae braf brat brea breb bree bref brer bret brrr btaa btaf btrt bttb eaaf eaba eafb eara earb eare eart eata eate ebba ebbr eber eeea eeee eefa eefe eera eeta eete efab efbr efet effa eft- efta eraf erat erba erbb erbe ereb erer eret erft erra erre erta etat etbr etee eter etfa etfb etfe etra etre etta ette faaa faba fabe faeb fafa fafe faff fara farb fare farr fart fata fate fatf fatt fbar feaf fear feat feba feeb feer feet fefe feff fera ferb fere ferr fert feta fete fetr fett ffar ffee ffff ffrr fftf frab frae frat frea free fret frta ftea fter raab raaf raat raba rabb rabe raef raer rafa rafe raff raft rara rarb rare rarf rata rate ratf ratt rbaf rbbb rbbr rea- reae reaf rear reat reba rebb rebe reeb reef reet refe reff refr reft rera rere rert reta rete retr rett rfae rfef rrat rrrr rtbf rtee rtfb taa- taaf taar taat taba tabb tabe taer tafa tafe taff taft tara tarb tare tarf tarr tart tata tatb tate tatr tatt tbaf tbar tbrb tbta tear teat teba teef teer teet teff teft ter- tera tere terf terr teta tete tetr tett tfae tfeb traa trab trae traf trat tre- trea tree tref tret trfr trra trte trtr ttab ttbb tter ttfa ttff tttt