-er a-a a-c aaa aac aae aak aam aan aao aar ac- aca acc ace ack acm acn aco acr aea aec aee aek aem aen aeo aer aka akc ake akk akm akn ako akr ama amc ame amk amm amn amo amr an- ana anc ane ank anm ann ano anr aoa aoc aoe aok aom aon aoo aor ar- ara arc are ark arm arn aro arr c-- caa cac cae cak cam can cao car cca ccc cce cck ccm ccn cco ccr ce- cea cec cee cek cem cen ceo cer cka ckc ckm cko cma cmc cme cmk cmm cmn cmo cmr cn- cna cnc cne cnm cnn cno cnr co- coa coc coe cok com con coo cor cra crc cre crk crm crn cro crr eaa eac eae eak eam ean eao ear ec- eca ecc ece eck ecm ecn eco ecr eea eec eee eek eem een eeo eer eka ekc eke eko ekr em- ema emc eme emk emm emn emo emr en- ena enc ene enk enm enn eno enr eo- eoa eoc eoe eok eom eon eoo eor era erc ere erk erm ern ero err ka- kaa kac kae kak kam kan kao kar kca kcc kce kck kcm kcn kcr ke- kea kec kee kek kem ken keo ker kkc kke kkk kkm kkn kkr kma kmc kme kmk kmm kmo kn- kna knc kne knk knm knn kno knr koa koc koe kok kom kon koo kor kra krc krk krn kro krr m-o m-r maa mac mae mak mam man mao mar mc- mca mcc mce mck mcm mcn mco mcr mea mec mee mek mem men meo mer mka mkc mke mkk mkm mkn mko mkr mma mmc mme mmk mmm mmn mmo mmr mna mnc mne mnk mnm mnn mno mnr moa moc moe mok mom mon moo mor mra mrc mre mrk mrm mrn mro mrr naa nac nae nak nam nan nao nar nca ncc nce nck ncm ncn nco ncr ne- nea nec nee nek nem nen neo ner nka nkc nke nkk nkm nkn nko nkr nma nmc nme nmk nmm nmn nmo nmr nna nnc nne nnk nnm nnn nno no- noa noc noe nok nom non noo nor nra nrc nre nrk nrm nrn nro nrr oaa oac oae oak oam oan oao oar oc- oca occ ock ocm ocn oco ocr oea oec oee oem oen oeo oer oka okc oke okk oko okr om- oma omc ome omm omn omo omr on- ona onc one onk onn ono onr oo- ooa ooc ook oom oon ooo oor or- ora orc ore ork orm orn oro orr ra- raa rac rae rak ram ran rao rar rca rcc rce rcm rcn rco rcr re- rea rec ree rek rem ren reo rer rkc rke rkk rkm rko rma rmc rme rmm rmn rmo rmr rna rnc rnm rnn rno rnr roa roc roe rok rom ron roo ror rra rrc rrk rrm rrn rrr