a-a a-b a-i aaa aab aaf aai aam ab- aba abb abf abi abm af- afa afb aff afi afm ai- aia aib aif aii aim ama amb amf ami amm baa bab baf bai bam bba bbb bbf bbi bbm bfa bfb bff bfi bfm bi- bia bib bif bii bim bma bmb bmf bmi bmm faa fab faf fai fam fba fbb fbf fbi fbm ffa fff ffi ffm fia fib fif fii fim fma fmb fmf fmi fmm i-f ia- iaa iab iaf iai iam iba ibb ibf ibi ibm ifa ifb iff ifi ifm iia iib iif iii iim im- ima imb imf imi imm m-f maa mab maf mai mam mba mbb mbf mbi mbm mfa mfb mff mfi mfm mi- mia mib mif mii mim mma mmb mmf mmi mmm