a-a a-b aaa aab aad aan aao aay ab- aba abb abd abn abo aby ad- ada adb add adn ado ady an- ana anb and ann ano any aoa aob aod aon aoo ay- aya ayd ayn ayo baa bab bad ban bao bay bba bbb bbd bbn bbo bby bda bdb bdd bdo bdy bna bnb bnd bnn bno boa bob bod bon boo boy by- bya byd byn byo daa dab dad dan dao day dba dbb dbd dbn dbo dby dda ddb ddd ddn ddo ddy dna dnb dnd dnn dno dny doa dob dod don doo doy dy- dya dyb dyd dyn dyo dyy naa nab nad nan nao nay nba nbb nbd nbn nbo nda ndb ndd ndn ndo ndy nna nnb nnn nno no- noa nob nod non noo noy nya nyd nyn nyo nyy oaa oab oad oan oao ob- oba obb obd obn obo oby oda odb odd odn odo on- ona onb ond onn ono ony oo- ooa oob ood oon ooo oya oyd oyo yaa yab yad yan yao yay yby yda ydn ydo ydy yna ynd ynn yny yob yod yon yoo yoy yyb yyy