a-a a-b a-i aaa aab aad aaf aai aan ab- aba abb abd abf abi abn ad- ada adb add adf adi adn af- afa afb afd aff afi afn ai- aia aib aid aif aii ain an- ana anb and anf ani ann baa bab bad baf bai ban bba bbb bbd bbf bbi bbn bda bdb bdd bdf bdi bfa bfb bfd bff bfi bfn bi- bia bib bid bif bii bin bna bnb bnd bnf bni bnn daa dab dad daf dai dan dba dbb dbd dbf dbi dbn dda ddb ddd ddf ddi ddn dfa dfb dfd dff dfi dfn di- dia dib did dif dii din dna dnb dnd dnf dni dnn faa fab fad faf fai fan fba fbb fbd fbf fbi fbn fda fdb fdd fdf fdi fdn ffa ffd fff ffi ffn fia fib fid fif fii fin fna fnb fnd fnf fni fnn i-d i-f ia- iaa iab iad iaf iai ian iba ibb ibd ibf ibi ibn ida idb idd idf idi idn ifa ifb ifd iff ifi ifn iia iib iid iif iii iin in- ina inb ind inf ini inn n-i naa nab nad naf nai nan nba nbb nbd nbf nbi nbn nda ndb ndd ndf ndi ndn nfa nfb nfd nff nfi nfn nia nib nid nif nii nin nna nnb nnf nni nnn