-er eee eek eep eer ees eet eke ekp ekr eks ekt ep- epe epp epr eps ept ere erk erp err ers ert es- ese esk esp esr ess est ete etk etp etr ets ett k-t ke- kee kek kep ker kes ket kke kkk kkp kkr kks kkt kpe kpk kpp kpr kps kpt krk krp krr krs krt kse ksk ksp ksr kss kst kte ktk ktp ktr kts ktt p-p pee pek pep per pes pet pke pkp pkr pks pkt ppe ppk ppp ppr pps ppt pre prk prp prr prs prt ps- pse psk psp psr pss pst pt- pte ptk ptp ptr pts ptt re- ree rek rep rer res ret rke rkk rkp rks rkt rpe rpk rpp rpr rps rpt rrk rrp rrr rrs rrt rse rsk rsp rsr rss rst rte rtk rtp rtr rts rtt se- see sek sep ser ses set sk- ske skk skp skr sks skt spe spk spp spr sps spt sr- sre srk srp srr srs srt ss- sse ssk ssp ssr sss sst ste stk stp str sts stt te- tee tek tep ter tes tet tke tkk tkp tkr tks tkt tpe tpk tpp tpr tps tpt tre trk trp trr trs trt tse tsk tsp tsr tss tst tte ttk ttp ttr tts ttt