a-a a-b a-z aaa aab aad aar aau aaz ab- aba abb abd abr abu abz ad- ada adb add adr adu adz ar- ara arb ard arr aru arz au- aua aub aud aur auz az- aza azb azd azu azz b-u baa bab bad bar bau baz bba bbb bbd bbr bbu bda bdb bdd bdr bdu bdz bra brb brd brr bru brz bua bub bud bur buu buz bza bzd bzr bzu bzz daa dab dad dar dau daz dba dbb dbd dbr dbu dbz dda ddb ddd ddr ddu ddz dra drb drd drr dru drz dua dub dud dur duz dza dzb dzd dzr dzu ra- raa rab rad rar rau raz rba rbb rbd rbr rbu rda rdb rdd rdr rdu rra rrb rrd rrr rru rua rub rud rur ruu ruz rza rzb ua- uaa uab uad uar uau uaz uba ubb ubr ubu uda udb udd udr udu ur- ura urb urd urr uru urz uua uur uuu uza uzb uzu zaa zab zad zar zaz zbb zbr zub zud zur zuz zzr zzz