a-be aaaa aaab aaae aaar aaba aabb aabt aaea aara aare aart aata aatt abaa abab abae abar abat abax abb- abba abbb abbe abbr abbt abee aber abet abra abta aeer aer- aera aeta aetr aett aetx arab arae arar arat arax arba arbe area aree aret arex arr- arra arre arrr arrt arta arte artr artx at-t at-x ataa atab atae atar atat atax atea atee ater atex atra atre atrx atta atte attr axar axat axer ba-x baaa baar baat baba babb babe babr baer bar- bara barb bare barr bart barx bata bate batt baxt bbbb bbeb bbet bear beat beba bebb bebe beeb beer beet bera bere berr bert beta bete bett brab brae brat brax brea breb bree brer bret brex brrr btaa btex btrt bttb eaba eara earb eare eart eata eate ebba ebbr eber eeea eeee eera eeta eete eext er-x erat erba erbb erbe ereb erer eret erra erre erta etat etbr etee eter etra etre etta ette exa- exer exrx exta exte extr raab raat raba rabb rabe raer rara rarb rare rata rate ratt raxa rbbb rbbr rea- reae rear reat reba rebb rebe reeb reet rera rere rert reta rete retr rett rexx rrat rrrr rtee rtex taa- taar taat taba tabb tabe taer tara tarb tare tarr tart tata tatb tate tatr tatt tax- taxa taxe taxt tbar tbrb tbta tear teat teba teer teet ter- tera tere terr teta tete tetr tett tetx texa text traa trab trae trat trax tre- trea tree tret trex trra trte trtr ttab ttbb tter tttt txaa txtr xaar xara xare xate xbar xbee xbra xeer xer- xera xert xexe xtar xtea xtra xxxx