aaaa aaab aaaf aaar aaba aabb aabt aafa aafb aaff aaoo aara aaro aart aata aatf aatt abaa abab abaf abar abat abb- abba abbb abbo abbr abbt abff aboa abob abof aboo abor abot abra abro abta afaa afao afar afat affa affo afft afoa afoo afor afr- afra afro afta aoba aora aorb aort aotf arab araf arar arat arba arfa arfb arff arft aroa arob aroo aror arr- arra arro arrr arrt arta arto artr at-t ataa atab atar atat atfb atob atof ator atot atra atro atta atto attr baaa baaf baar baat baba babb babo babr baff bafo baft bar- bara barb barf baro barr bart bata batf bato batt bbbb bfta bftt boab boar boat boba bobb bobo bofa boff boob boof boor boot bor- bora borf boro borr bort bota botb boto bott brab braf brao brat broa brob broo bror brot brrr btaa btaf btob btor btrt bttb faaa faba fabo fafa faff fafo fara farb faro farr fart fata fatf fato fatt fbar ffar ffff ffrr fftf foaf foar foba fobt fofo foof foot for- fora forb foro forr fort fota foto fott frab frat frob frot frta oafo oara obba obbo obor obot obra obro off- offa offo offr ofor ofra ofta ooaa ooba ooff oooo oora oort ootb orab orao orar orat orba orbb orbo orff oro- orof oror orot orra orro orta orto otar oto- otof otoo otor otra otro otta otto raab raaf raat raba rabb rabo rafa raff raft raob rara rarb rarf raro rata ratf rato ratt rbaf rbbb rbbr roab roaf roar roat rob- roba robb robo robt roff rofo roob roof roor root rora roro rort rota roto rotr rott rrat rrrr rtbf rtfb taa- taaf taar taat taba tabb tabo tafa taff tafo taft taoa taor tara tarb tarf taro tarr tart tata tatb tato tatr tatt tbaf tbar tbrb tbta tfot toab toat toba tobo tobt tofa toff tofo toft tooa toof toor toot tora torf toro torr tort tota toto totr tott traa trab traf trao trat trfr troa troo trot trra trtr ttab ttbb ttfa ttff tttt