-er a-a a-c a-t aaa aac aad aae aaf aak aar aas aat ac- aca acc acd ace acf ack acr acs act ad- ada adc add ade adf adk adr ads adt aea aec aed aee aef aek aer aes aet af- afa afc afd afe aff afk afr afs aft aka akc akd ake akk akr aks ar- ara arc ard are arf ark arr ars art as- asa asc asd ase asf ask asr ass ast at- ata atc atd ate atf atr ats att c-- caa cac cad cae caf cak car cas cat cca ccc ccd cce ccf cck ccr ccs cct cda cdc cdd cde cdf cdk cdr cds cdt ce- cea cec ced cee cef cek cer ces cet cfa cfc cfd cfe cff cfk cfr cfs cft cka ckc ckd cks ckt cra crc crd cre crf crk crr crs crt csa csc csd cse csf csk csr css cst cta ctc ctd cte ctf ctk ctr cts ctt daa dac dad dae daf dak dar das dat dca dcc dcd dce dcf dck dcr dcs dct dda ddc ddd dde ddf ddk ddr dds ddt de- dea dec ded dee def dek der des det dfa dfc dfd dfe dff dfk dfr dfs dft dka dkc dke dkk dkr dks dkt dra drc drd dre drk drr drs drt dsa dsc dsd dse dsf dsk dsr dss dst dta dtc dtd dte dtf dtk dtr dts dtt eaa eac ead eae eaf eak ear eas eat ec- eca ecc ecd ece ecf eck ecr ecs ect ed- eda edc edd ede edf edk edr eds edt eea eec eed eee eef eek eer ees eet ef- efa efc efd efe eff efr efs eft eka ekc ekd eke ekf ekr eks ekt era erc erd ere erf erk err ers ert es- esa esc esd ese esf esk esr ess est eta etc etd ete etf etk etr ets ett faa fac fad fae faf fak far fas fat fca fcc fcd fce fcf fck fcr fcs fct fda fdc fdd fde fdf fdk fdr fds fdt fea fec fed fee fef fek fer fes fet ffa ffc ffd ffe fff ffk ffr ffs fft fka fkc fkf fkk fkt fra frc frd fre frf frk frr frs frt fsa fsc fsd fse fsf fsk fsr fss fst fta ftc ftd fte ftf ftk ftr fts ftt k-t ka- kaa kac kad kae kaf kak kar kas kat kca kcc kcd kce kck kcr kcs kct kda kdc kde kdf kdk kdr kds kdt ke- kea kec ked kee kef kek ker kes ket kfa kfc kfd kff kfs kkc kke kkk kkr kks kkt kra krc krd krf krk krr krs krt ksa ksc ksd kse ksf ksk ksr kss kst kta ktc kte ktf ktk ktr kts ktt ra- raa rac rad rae raf rak rar ras rat rca rcc rcd rce rcf rcr rcs rct rda rdc rdd rde rdf rdr rds rdt re- rea rec red ree ref rek rer res ret rfa rfc rfd rfe rff rfk rfr rfs rft rkc rke rkf rkk rks rkt rra rrc rrd rrf rrk rrr rrs rrt rsa rsc rsd rse rsf rsk rsr rss rst rta rtc rtd rte rtf rtk rtr rts rtt saa sac sad sae saf sak sar sas sat sca scc scd sce scf sck scr scs sct sda sdc sdd sde sdf sdk sdr sds sdt se- sea sec sed see sef sek ser ses set sfa sfc sfd sfe sff sfk sfr sfs sft sk- ska skc skd ske skf skk skr sks skt sr- sra src srd sre srf srk srr srs srt ss- ssa ssc ssd sse ssf ssk ssr sss sst sta stc std ste stf stk str sts stt taa tac tad tae taf tak tar tas tat tca tcc tcd tce tcf tck tcr tcs tct tda tdc tdd tde tdf tdk tdr tds tdt te- tea tec ted tee tef tek ter tes tet tfa tfc tfd tfe tff tfk tfr tfs tft tka tkc tke tkk tkr tks tkt tra trc trd tre trf trk trr trs trt tsa tsc tsd tse tsf tsk tsr tss tst tta ttc ttd tte ttf ttk ttr tts ttt