a-a a-b a-z aaa aab aao aar aau aay aaz ab- aba abb abo abr abu aby abz aoa aob aoo aor aou ar- ara arb aro arr aru ary arz au- aua aub auo aur auz ay- aya ayo ayr ayu ayz az- aza azb azo azu azy azz b-u baa bab bao bar bau bay baz bba bbb bbo bbr bbu bby boa bob boo bor bou boy boz bra brb bro brr bru bry brz bua bub buo bur buu buy buz by- bya byo byr byu byz bza bzo bzr bzu bzz oaa oab oao oar oau ob- oba obb obo obr obu oby oo- ooa oob ooo oor or- ora orb oro orr oru ory orz ou- oua ouo our oya oyo oza ozo ozu ozz ra- raa rab rao rar rau ray raz rba rbb rbo rbr rbu roa rob roo ror rou roy roz rra rrb rrr rru rua rub ruo rur ruu ruy ruz ry- rya ryo ryr ryu ryy ryz rza rzb rzo rzy ua- uaa uab uao uar uau uay uaz uba ubb ubo ubr ubu uby uoa uob uoo uor ur- ura urb uro urr uru ury urz uua uur uuu uyo uyu uza uzb uzo uzu yaa yab yao yar yau yay yaz ybr yby ybz yob yoo yor you yoy yra yro yru yua yuo yur yuu yuy yyb yyu yyy yyz yzb yzr yzu yzy zaa zab zao zar zay zaz zbb zbr zby zo- zoa zob zoo zor zou zro zub zur zuz zzr zzy zzz