-er -ic bbb bbc bbe bbi bbk bbm bbo bbr bcb bcc bce bci bck bcm bco bcr be- beb bec bee bei bek bem beo ber bi- bib bic bie bii bik bim bio bir bkb bkc bke bkk bkm bko bkr bmb bmc bme bmi bmk bmm bmo bmr bob boc boe boi bok bom boo bor brb bre bri brk brm bro brr c-- cbb cbc cbe cbi cbk cbm cbo cbr ccb ccc cce cci cck ccm cco ccr ce- ceb cec cee cei cek cem ceo cer ci- cib cic cie cii cik cim cio cir ckb ckc cki ckm cko cmb cmc cme cmi cmk cmm cmo cmr co- cob coc coe coi cok com coo cor crb crc cre cri crk crm cro crr ebb ebc ebe ebi ebk ebm ebo ebr ec- ecb ecc ece eci eck ecm eco ecr eeb eec eee eek eem eeo eer eib eic eie eii eik eim eio eir ekb ekc eke eki eko ekr em- emb emc eme emi emk emm emo emr eo- eob eoc eoe eoi eok eom eoo eor erb erc ere eri erk erm ero err ibb ibc ibe ibi ibk ibm ibo ibr icb icc ice ici ick icm ico icr ie- iec iee iei iek iem ier iib iic iie iii iim iio iir ikb ikc ike iki ikk iko ikr im- imb imc ime imi imm imo io- iob ioc ioe ioi iom ioo ior ir- irb irc ire iri irk irm iro irr kbb kbc kbe kbi kbk kbm kbo kbr kcb kcc kce kci kck kcm kcr ke- keb kec kee kei kek kem keo ker kib kic kie kii kik kim kio kir kkb kkc kke kki kkk kkm kkr kmb kmc kme kmi kmk kmm kmo kob koc koe koi kok kom koo kor krc kri krk kro krr m-o m-r mbb mbc mbe mbi mbk mbm mbo mbr mc- mcb mcc mce mci mck mcm mco mcr meb mec mee mei mek mem meo mer mi- mib mic mie mii mik mim mio mir mkb mkc mke mkk mkm mko mkr mmb mmc mme mmi mmk mmm mmo mmr mob moc moe moi mok mom moo mor mrb mrc mre mri mrk mrm mro mrr o-i ob- obb obc obe obi obk obm obo obr oc- ocb occ oci ock ocm oco ocr oeb oec oee oei oem oeo oer oib oic oie oii oik oim oio oir okb okc oke oki okk oko okr om- omb omc ome omi omm omo omr oo- oob ooc ooi ook oom ooo oor or- orb orc ore ori ork orm oro orr rbb rbc rbe rbi rbk rbm rbo rbr rcb rcc rce rci rcm rco rcr re- reb rec ree rei rek rem reo rer rib ric rie rii rik rim rio rir rkb rkc rke rkk rkm rko rmb rmc rme rmi rmm rmo rmr rob roc roe roi rok rom roo ror rrb rrc rri rrk rrm rrr