-er -ol eee eef eek eel eeo eer ef- efe eff efl efo efr eke ekf ekl eko ekr ele elf elk ell elo elr eo- eoe eof eok eol eoo eor ere erf erk erl ero err fee fef fek fel feo fer ffe fff ffk ffl ffo ffr fkf fkk fkl fle flf fll flo flr foe fof fok fol foo for fre frf frk frl fro frr ke- kee kef kek kel keo ker kff kfo kke kkk kkl kkr kl- klf klo klr koe kof kok kol koo kor krf krk krl kro krr lee lef lek lel leo ler lfe lff lfk lfl lfo lfr lkl lkr lle llf llk lll llo llr loe lof lok lol loo lor lrf lrk lro lrr oee oef oel oeo oer of- ofe off ofl ofo ofr oke okk okl oko okr ole olf olk oll olo oo- oof ook ool ooo oor or- ore orf ork orl oro orr re- ree ref rek rel reo rer rfe rff rfk rfl rfo rfr rke rkf rkk rko rle rlf rll rlo rlr roe rof rok rol roo ror rrf rrk rrl rrr