a-a a-b aaa aab aad aag aan ab- aba abb abd abg abn ad- ada adb add adg adn ag- aga agb agd agg agn an- ana anb and ang ann baa bab bad bag ban bba bbb bbd bbg bbn bda bdb bdd bdg bga bgb bgd bgg bgn bna bnb bnd bng bnn daa dab dad dag dan dba dbb dbd dbg dbn dda ddb ddd ddg ddn dga dgd dgg dgn dna dnb dnd dng dnn g-d gaa gab gad gag gan gba gbd gbg gbn gda gdb gdd gdn gga ggb ggd ggg ggn gna gnb gnd gnn naa nab nad nag nan nba nbb nbd nbg nbn nda ndb ndd ndg ndn nga ngb ngd ngg ngn nna nnb nng nnn