-ey a-a a-b a-t aaa aab aae aat aax aay ab- aba abb abe abt abx aby aea aeb aee aet aex aey at- ata atb ate att atx ax- axa axe axt axx ay- aya aye ayt ayx baa bab bae bat bax bay bba bbb bbe bbt bbx bby be- bea beb bee bet bex bey bta btb bte btt btx bty bxb bxx by- bya bye byt eaa eab eae eat eax eba ebb ebe ebt ebx eby eea eeb eee eet eex eey eta etb ete ett etx ety ex- exa exe ext exx exy eya eye eyt t-x taa tab tae tat tax tay tba tbb tbe tbt te- tea teb tee tet tex tey tta ttb tte ttt ttx tty txe txt tya tye tyt xaa xat xbe xbx xee xet xex xtx xty xxx xxy xyy yaa yab yae yat yax yay ybe yby yea yeb yee yet yex yey yta yte ytt yxa yxe yxy yyb yye yyt yyy