-er -ol c-- ccc cce ccf cck ccl cco ccr ccs ce- cec cee cef cek cel ceo cer ces cfc cfe cff cfk cfl cfo cfr cfs ckc cko cks cl- clc cle clf clk cll clo clr cls co- coc coe cof cok col coo cor cos crc cre crf crk crl cro crr crs csc cse csf csk csl cso csr css ec- ecc ece ecf eck ecl eco ecr ecs eec eee eef eek eel eeo eer ees ef- efc efe eff efl efo efr efs ekc eke ekf ekl eko ekr eks elc ele elf elk ell elo elr els eo- eoc eoe eof eok eol eoo eor eos erc ere erf erk erl ero err ers es- esc ese esf esk esl eso esr ess fcc fce fcf fck fcl fco fcr fcs fec fee fef fek fel feo fer fes ffc ffe fff ffk ffl ffo ffr ffs fkc fkf fkk fkl flc fle flf fll flo flr fls foc foe fof fok fol foo for fos frc fre frf frk frl fro frr frs fsc fse fsf fsk fsl fso fsr fss kcc kce kck kcl kcr kcs ke- kec kee kef kek kel keo ker kes kfc kff kfo kfs kkc kke kkk kkl kkr kks kl- klc klf klo klr kls koc koe kof kok kol koo kor kos krc krf krk krl kro krr krs ksc kse ksf ksk ksl kso ksr kss lcc lce lcf lck lcl lco lcr lcs lec lee lef lek lel leo ler les lfc lfe lff lfk lfl lfo lfr lfs lkl lkr lks llc lle llf llk lll llo llr lls loc loe lof lok lol loo lor los lrc lrf lrk lro lrr lrs lsc lse lsf lsk lsl lso lsr lss oc- occ ocf ock ocl oco ocr ocs oec oee oef oel oeo oer oes of- ofc ofe off ofl ofo ofr ofs okc oke okk okl oko okr oks olc ole olf olk oll olo ols oo- ooc oof ook ool ooo oor oos or- orc ore orf ork orl oro orr ors os- osc ose osf osk osl oso osr oss rcc rce rcf rcl rco rcr rcs re- rec ree ref rek rel reo rer res rfc rfe rff rfk rfl rfo rfr rfs rkc rke rkf rkk rko rks rlc rle rlf rll rlo rlr rls roc roe rof rok rol roo ror ros rrc rrf rrk rrl rrr rrs rsc rse rsf rsk rsl rso rsr rss scc sce scf sck scl sco scr scs se- sec see sef sek sel seo ser ses sfc sfe sff sfk sfl sfo sfr sfs sk- skc ske skf skk skl sko skr sks slc sle slf slk sll slo slr sls soc soe sof sok sol soo sor sos sr- src sre srf srk srl sro srr srs ss- ssc sse ssf ssk ssl sso ssr sss