-er c-- ccc cce cck ccm cco ccr ccz ce- cec cee cek cem ceo cer cez ckc ckm cko cmc cme cmk cmm cmo cmr co- coc coe cok com coo cor coz crc cre crk crm cro crr crz cz- czc cze czk czm czo ec- ecc ece eck ecm eco ecr eec eee eek eem eeo eer ekc eke eko ekr em- emc eme emk emm emo emr eo- eoc eoe eok eom eoo eor erc ere erk erm ero err erz eze ezo ezr ezz k-z kcc kce kck kcm kcr ke- kec kee kek kem keo ker kez kkc kke kkk kkm kkr kmc kme kmk kmm kmo kmz koc koe kok kom koo kor koz krc krk kro krr kzo m-o m-r mc- mcc mce mck mcm mco mcr mcz mec mee mek mem meo mer mez mkc mke mkk mkm mko mkr mkz mmc mme mmk mmm mmo mmr mmz moc moe mok mom moo mor moz mrc mre mrk mrm mro mrr mrz mzm oc- occ ock ocm oco ocr ocz oec oee oem oeo oer okc oke okk oko okr om- omc ome omm omo omr omz oo- ooc ook oom ooo oor or- orc ore ork orm oro orr orz oze ozm ozo ozz rcc rce rcm rco rcr re- rec ree rek rem reo rer rez rkc rke rkk rkm rko rkz rmc rme rmm rmo rmr roc roe rok rom roo ror roz rrc rrk rrm rrr rze rzm rzo zce zco zec zee zek zem zeo zer zez zmc zmk zmm zo- zoc zoe zok zom zoo zor zro zzr zzz