a-a a-b a-t aaa aab aak aas aat aay ab- aba abb abk abs abt aby aka akb akk aks as- asa asb ask ass ast asy at- ata atb ats att ay- aya ayk ays ayt baa bab bak bas bat bay bba bbb bbk bbs bbt bby bka bkb bkk bks bkt bsa bsb bsk bss bst bsy bta btb btk bts btt bty by- bya byk bys byt k-t ka- kaa kab kak kas kat kay kba kbb kbk kbs kkb kkk kks kkt kky ksa ksb ksk kss kst kta ktb ktk kts ktt kya kys kyt saa sab sak sas sat say sba sbb sbk sbs sbt sby sk- ska skb skk sks skt sky ss- ssa ssb ssk sss sst sta stb stk sts stt sty sy- sya syb syk sys syt taa tab tak tas tat tay tba tbb tbk tbs tbt tka tkb tkk tks tkt tky tsa tsb tsk tss tst tsy tta ttb ttk tts ttt tty tya tys tyt yaa yab yak yas yat yay ybs yby yka ykk ysa ysb ysk yss yst ysy yta ytk yts ytt yyb yys yyt yyy