a-a a-b a-t a-z aaa aab aao aat aav aaz ab- aba abb abo abt abv abz aoa aob aoo aot aov at- ata atb ato att atv atz av- ava avb avo avt avz az- aza azb azo azt azz baa bab bao bat bav baz bba bbb bbo bbt boa bob boo bot bov boz bta btb bto btt btv btz bva bvb bvo bvt bvv bza bzo bzz oaa oab oao oat oav ob- oba obb obo obt obv oo- ooa oob ooo oot oov ot- ota otb oto ott otv otz ov- ova ovb ovo ovv oza ozo ozt ozz taa tab tao tat tav taz tba tbb tbo tbt tbv tbz to- toa tob too tot tov toz tta ttb tto ttt ttv tva tvb tvo tvt tvz tza v-a vaa vab vao vat vav vaz vba vbo vbv vbz voa vob voo vot vov voz vta vtb vto vtt vtv vtz vva vvb vvo vvt vvv vvz zaa zab zao zat zav zaz zbb zbt zbv zo- zoa zob zoo zot zta ztv zzt zzz