a-fu aaaa aaab aaaf aaas aaba aabb aabt aafa aafb aaff aasa aasf aass aast aasu aata aatf aatt aaus abaa abab abaf abas abat abau abb- abba abbb abbs abbt abff abs- absa absf abss absu abta abts abtu abua abuf abus abut afaa afat afbs affa affs afft afsa afsb afst afta afts afua afus asaa asab asaf asas asat asau asba asbu asfa assa asss asst assu asta astb asts asub asus at-t ataa atab atas atat atbs atfb atfs atsb atst atta atts attu atua atub atus auaa aufs ausa aust ausu aut- auts baaa baaf baas baat baba babb babs babu baff baft basa basf bass bast basu bata batf bats batt batu bau- bauf bbas bbau bbbb bbbs bfas bffs bfta bfts bftt bsaa bsas bsat bsfa bsff bsfs bsts btaa btaf btss bttb btus buat buba bubb bubs bubu buff busa buss bust busu but- buta buts butt buus faaa faas faba fabs fabu fafa faff fasa fass fast fata fatf fats fatt faut fbus ffff ffsa ffss fftf fsas fssa fssf fsta ftsa ftub fuat fubb fubs fubu fuff fufu fusa fuss fust fusu futa futs futu saab saaf saas saat saba sabb sabs sabu safa safb saff saft safu sasa sasf sass sast sata satb sats satt satu saua sauf saus saut sbaa sbas sbbs sbsa sbst sbus sfas sfba sfss sfsu sfts ssaa ssab ssas ssat ssau sssa sssb sssf ssss ssta sstb ssts stab stas stat stau stbs stfu stsf stss stub stuf stus stut suas suat sub- suba subb subs suf- sufa suff sufs sufu sus- susa suss sust susu suta sutu suus taa- taaf taas taat taba tabb tabs tabu tafa taff taft tasa tasb tass tast tasu tata tatb tats tatt tatu taua taub taus taut tbaf tbas tbbs tbst tbta tfss tsaa tsat tsau tssa tssf tsst tsts ttab ttbb ttfa ttff ttss tttt tuas tuat tuba tubb tubs tubu tufa tuff tuft tufu tusa tuss tust tuta tuts tutt tutu uafa uasa uata uatu uaua ubba ubtf uffa us-a usaa usaf usas usat usba usbs usfa usfs ussa ussb ussf usss usst ussu usta ustb usts usua usus utas utau utsa uttu uuta uutf uuuu