a-a a-b aaa aab aaf aar aas aau aay ab- aba abb abf abr abs abu aby af- afa afb aff afr afs afu afy ar- ara arb arf arr ars aru ary as- asa asb asf asr ass asu asy au- aua aub auf aur aus ay- aya ayf ayr ays ayu b-u baa bab baf bar bas bau bay bba bbb bbf bbr bbs bbu bby bfa bfb bff bfr bfs bfu bfy bra brb brf brr brs bru bry bsa bsb bsf bsr bss bsu bsy bua bub buf bur bus buu buy by- bya byf byr bys byu faa fab faf far fas fau fay fba fbb fbf fbr fbs fbu ffa fff ffr ffs ffu ffy fra frb frf frr frs fru fry fsa fsb fsf fsr fss fsu fua fub fuf fur fus fuu fy- fya fyb ra- raa rab raf rar ras rau ray rba rbb rbf rbr rbs rbu rfa rfb rff rfr rfs rfu rra rrb rrf rrr rrs rru rsa rsb rsf rsr rss rsu rua rub ruf rur rus ruu ruy ry- rya ryf ryr rys ryu ryy saa sab saf sar sas sau say sba sbb sbf sbr sbs sbu sby sfa sfb sff sfr sfs sfu sr- sra srb srf srr srs sry ss- ssa ssb ssf ssr sss ssu sua sub suf sur sus suu suy sy- sya syb syr sys syu ua- uaa uab uaf uar uas uau uay uba ubb ubf ubr ubs ubu uby ufa uff ufr ufs ufu ur- ura urb urf urr urs uru ury usa usb usf usr uss usu uua uur uus uuu uys uyu yaa yab yaf yar yas yau yay ybf ybr ybs yby yfa yff yfr yfs yfu yra yrf yrs yru ysa ysb ysr yss ysu ysy yua yur yus yuu yuy yyb yyf yys yyu yyy