a-a a-b a-z aaa aab aag aao aar aay aaz ab- aba abb abg abo abr aby abz ag- aga agb agg ago agr agy agz aoa aob aog aoo aor ar- ara arb arg aro arr ary arz ay- aya ayo ayr ayz az- aza azb azg azo azy azz baa bab bag bao bar bay baz bba bbb bbg bbo bbr bby bga bgb bgg bgo bgr bgz boa bob bog boo bor boy boz bra brb brg bro brr bry brz by- bya byg byo byr byz bza bzo bzr bzz gaa gab gag gao gar gay gaz gba gbg gbo gbr gby gbz gga ggb ggg ggo ggr ggz goa gob gog goo gor goy goz gra grb grg gro grr gry gy- gya gyb gyo gyr gza gzo gzr oaa oab oag oao oar ob- oba obb obg obo obr oby oga ogg ogo ogy oo- ooa oob oog ooo oor or- ora orb org oro orr ory orz oya oyo oza ozo ozz ra- raa rab rag rao rar ray raz rba rbb rbg rbo rbr rga rgb rgg rgo rgr roa rob rog roo ror roy roz rra rrb rrg rrr ry- rya ryg ryo ryr ryy ryz rza rzb rzo rzy yaa yab yag yao yar yay yaz ybg ybr yby ybz yga ygo yob yog yoo yor yoy yra yrg yro yyb yyg yyy yyz yzb yzr yzy z-g zaa zab zag zao zar zay zaz zbb zbr zby zgb zgg zo- zoa zob zog zoo zor zro zzr zzy zzz