-er a-a a-b a-t a-z aaa aab aae aak aar aat aaz ab- aba abb abe abk abr abt abz aea aeb aee aek aer aet aez aka akb ake akk akr ar- ara arb are ark arr art arz at- ata atb ate atr att atz az- aza azb aze azt azz baa bab bae bak bar bat baz bba bbb bbe bbk bbr bbt be- bea beb bee bek ber bet bez bka bkb bke bkk bkr bkt bra brb bre brk brr brt brz bta btb bte btk btr btt btz bza bze bzr bzz eaa eab eae eak ear eat eaz eba ebb ebe ebk ebr ebt eea eeb eee eek eer eet eka ekb eke ekr ekt era erb ere erk err ert erz eta etb ete etk etr ett etz eze ezr ezz k-t k-z ka- kaa kab kae kak kar kat kaz kba kbb kbe kbk kbr kbz ke- kea keb kee kek ker ket kez kkb kke kkk kkr kkt kra krk krr krt kta ktb kte ktk ktr ktt ra- raa rab rae rak rar rat raz rba rbb rbe rbk rbr rbt re- rea reb ree rek rer ret rez rkb rke rkk rkt rkz rra rrb rrk rrr rrt rta rtb rte rtk rtr rtt rtz rza rzb rze taa tab tae tak tar tat taz tba tbb tbe tbk tbr tbt tbz te- tea teb tee tek ter tet tez tka tkb tke tkk tkr tkt tkz tra trb tre trk trr trt trz tta ttb tte ttk ttr ttt tza tze zaa zab zak zar zat zaz zbb zbr zbt zea zeb zee zek zer zet zez zka zta zte ztr zzr zzt zzz