a-a a-b a-t a-z aaa aab aar aat aay aaz ab- aba abb abr abt aby abz ar- ara arb arr art ary arz at- ata atb atr att atz ay- aya ayr ayt ayz az- aza azb azt azy azz baa bab bar bat bay baz bba bbb bbr bbt bby bra brb brr brt bry brz bta btb btr btt bty btz by- bya byr byt byz bza bzr bzz ra- raa rab rar rat ray raz rba rbb rbr rbt rra rrb rrr rrt rta rtb rtr rtt rty rtz ry- rya ryr ryy ryz rza rzb rzy taa tab tar tat tay taz tba tbb tbr tbt tbz tra trb trr trt try trz tta ttb ttr ttt tty tya tyr tyt tza yaa yab yar yat yay yaz ybr yby ybz yra yrt yta ytr ytt yyb yyt yyy yyz yzb yzr yzy zaa zab zar zat zay zaz zbb zbr zbt zby zta ztr zzr zzt zzy zzz