a-a a-b aaa aab aad aah aan ab- aba abb abd abh abn ad- ada adb add adh adn aha ahb ahd ahh ahn an- ana anb and anh ann baa bab bad bah ban bba bbb bbd bbh bbn bda bdb bdd bdh bha bhb bhd bhh bna bnb bnd bnn daa dab dad dah dan dba dbb dbd dbh dbn dda ddb ddd ddh ddn dh- dha dhb dhd dhh dna dnb dnd dnh dnn haa hab had hah han hba hbb hbd hbh hbn hda hdb hdd hdh hdn hha hhb hhd hhh hhn hna hnb hnd hnh hnn naa nab nad nah nan nba nbb nbd nbn nda ndb ndd ndh ndn nha nhb nhd nhh nhn nna nnb nnh nnn