-er eee eef eek eeo eep eer ees eet ef- efe eff efo efp efr efs eft eke ekf eko ekp ekr eks ekt eo- eoe eof eok eoo eop eor eos eot ep- epe epf epo epp epr eps ept ere erf erk ero erp err ers ert es- ese esf esk eso esp esr ess est ete etf etk eto etp etr ets ett fee fef fek feo fep fer fes fet ffe fff ffk ffo ffp ffr ffs fft fkf fkk fkp fkt foe fof fok foo fop for fos fot fpe fpk fpo fpp fpr fps fpt fre frf frk fro frp frr frs frt fse fsf fsk fso fsp fsr fss fst fte ftf ftk fto ftp ftr fts ftt k-t ke- kee kef kek keo kep ker kes ket kff kfo kfs kke kkk kkp kkr kks kkt koe kof kok koo kop kor kos kot kpe kpf kpk kpo kpp kpr kps kpt krf krk kro krp krr krs krt kse ksf ksk kso ksp ksr kss kst kte ktf ktk kto ktp ktr kts ktt oee oef oeo oep oer oes oet of- ofe off ofo ofp ofr ofs oft oke okk oko okp okr oks oo- oof ook ooo oop oor oos oot op- ope opf opk opo opp opr ops opt or- ore orf ork oro orp orr ors ort os- ose osf osk oso osp osr oss ost ot- ote otf otk oto otp otr ots ott p-p pee pef pek peo pep per pes pet pfe pff pfk pfo pfp pfr pfs pft pke pkf pko pkp pkr pks pkt poe pof pok poo pop por pos pot ppe ppf ppk ppo ppp ppr pps ppt pre prf prk pro prp prr prs prt ps- pse psf psk pso psp psr pss pst pt- pte ptf ptk pto ptp ptr pts ptt re- ree ref rek reo rep rer res ret rfe rff rfk rfo rfp rfr rfs rft rke rkf rkk rko rkp rks rkt roe rof rok roo rop ror ros rot rpe rpf rpk rpo rpp rpr rps rpt rrf rrk rrp rrr rrs rrt rse rsf rsk rso rsp rsr rss rst rte rtf rtk rto rtp rtr rts rtt se- see sef sek seo sep ser ses set sfe sff sfk sfo sfp sfr sfs sft sk- ske skf skk sko skp skr sks skt soe sof sok soo sop sor sos sot spe spf spk spo spp spr sps spt sr- sre srf srk sro srp srr srs srt ss- sse ssf ssk sso ssp ssr sss sst ste stf stk sto stp str sts stt te- tee tef tek teo tep ter tes tet tfe tff tfk tfo tfp tfr tfs tft tke tkk tko tkp tkr tks tkt to- toe tof tok too top tor tos tot tpe tpf tpk tpo tpp tpr tps tpt tre trf trk tro trp trr trs trt tse tsf tsk tso tsp tsr tss tst tte ttf ttk tto ttp ttr tts ttt