a-a a-b a-z aaa aab aah aao aar aaz ab- aba abb abh abo abr abz aha ahb ahh aho ahr ahz aoa aob aoh aoo aor ar- ara arb arh aro arr arz az- aza azb azo azz baa bab bah bao bar baz bba bbb bbh bbo bbr bha bhb bhh bho bhr boa bob boh boo bor boz bra brb brh bro brr brz bza bzh bzo bzr bzz haa hab hah hao har haz hba hbb hbh hbo hbr hbz hha hhb hhh hho hhr hhz hoa hob hoh hoo hor hr- hra hrb hrh hro hrr hrz hzo oaa oab oah oao oar ob- oba obb obh obo obr oha ohh oho ohr oo- ooa oob ooh ooo oor or- ora orb orh oro orr orz oza ozo ozz ra- raa rab rah rao rar raz rba rbb rbh rbo rbr rh- rha rhb rhh rho rhr roa rob roh roo ror roz rra rrb rrh rrr rza rzb rzo zaa zab zah zao zar zaz zbb zbr zha zho zhr zo- zoa zob zoo zor zrh zro zzr zzz