a-be aaaa aaab aaae aaam aaar aaba aabb aabm aaea aaem aama aamb aame aamr aara aare aarm abaa abab abae abam abar abax abb- abba abbb abbe abbr abee aber abma abmb abra aeer aer- aera amaa amae amam amar amax amb- amba ambe ambr ambx amee amer amex amm- amma amme amra arab arae aram arar arax arba arbe area aree arem arex arma arme armm arr- arra arre arrr axar axer ba-x baaa baam baar baba babb babe babm babr baer bama bamb bame bamm bar- bara barb bare barm barr barx bbbb bbeb beam bear beba bebb bebe beeb beem beer bema beme bera bere berm berr bmaa brab brae bram brax brea breb bree brem brer brex brrm brrr eaba eama eame eara earb eare ebam ebba ebbr eber eeea eeee eera emae emam emar emax emba embe embr emer emex emma emme emra emre er-x eram erba erbb erbe ereb erem erer erma erme erra erre exa- exam exer exmr exrx maaa maam maar maba mabe maee maem maer mama mame mar- mara mare marm marr marx maxx mbam mbba mear mebe meem meer mema meme memr memx mer- mera merb mere merm mexx mmaa mmab mmar mmea mmmm mmxx mrbb mrbm mreb mree raab raam raba rabb rabe raer rama ramb rame ramm rara rarb rare raxa rbbb rbbr rbmx rea- reae ream rear reba rebb rebe reeb reem rema reme rera rere rexx rrrr xaar xara xare xbar xbee xbra xeer xema xeme xer- xera xexe xmax xxxx