a-a a-i a-t aaa aaf aai aas aat aax af- afa aff afi afs aft afx ai- aia aif aii ais ait aix as- asa asf asi ass ast asx at- ata atf ati ats att atx ax- axa axi axs axt axx faa faf fai fas fat fax ffa fff ffi ffs fft ffx fia fif fii fis fit fix fsa fsf fsi fss fst fsx fta ftf fti fts ftt ftx fxi fxs fxt fxx i-f ia- iaa iaf iai ias iat ifa iff ifi ifs ift ifx iia iif iii iis iit iix is- isa isf isi iss ist ita itf iti its itt itx ixi saa saf sai sas sat sax sfa sff sfi sfs sft sfx sia sif sii sis sit six ss- ssa ssf ssi sss sst ssx sta stf sti sts stt stx sxi sxs sxt t-x taa taf tai tas tat tax tfa tff tfi tfs tft tfx tia tif tii tis tit tix tsa tsf tsi tss tst tsx tta ttf tti tts ttt ttx txf txi txs txt xaa xaf xas xat xfa xfs xft xfx xia xii xis xit xix xsa xsi xss xst xtf xti xts xtx xxi xxx