-er -ic c-- ccc ccd cce cci cck cco ccr ccs cdc cdd cde cdi cdk cdo cdr cds ce- cec ced cee cei cek ceo cer ces ci- cic cid cie cii cik cio cir cis ckc ckd cki cko cks co- coc cod coe coi cok coo cor cos crc crd cre cri crk cro crr crs csc csd cse csi csk cso csr css dcc dcd dce dci dck dco dcr dcs ddc ddd dde ddi ddk ddo ddr dds de- dec ded dee dei dek deo der des di- dic did die dii dik dio dir dis dkc dke dki dkk dko dkr dks doc dod doe doi dok doo dor dos drc drd dre dri drk dro drr drs dsc dsd dse dsi dsk dso dsr dss ec- ecc ecd ece eci eck eco ecr ecs ed- edc edd ede edi edk edo edr eds eec eed eee eek eeo eer ees eic eid eie eii eik eio eir eis ekc ekd eke eki eko ekr eks eo- eoc eod eoe eoi eok eoo eor eos erc erd ere eri erk ero err ers es- esc esd ese esi esk eso esr ess i-d icc icd ice ici ick ico icr ics idc idd ide idi idk ido idr ids ie- iec ied iee iei iek ier ies iic iid iie iii iio iir iis ikc ike iki ikk iko ikr iks io- ioc iod ioe ioi ioo ior ios ir- irc ird ire iri irk iro irr irs is- isc isd ise isi isk iso isr iss kcc kcd kce kci kck kcr kcs kdc kde kdk kdo kdr kds ke- kec ked kee kei kek keo ker kes kic kid kie kii kik kio kir kis kkc kke kki kkk kkr kks koc kod koe koi kok koo kor kos krc krd kri krk kro krr krs ksc ksd kse ksi ksk kso ksr kss o-i oc- occ ocd oci ock oco ocr ocs odc odd ode odi odo odr ods oec oed oee oei oeo oer oes oic oid oie oii oik oio oir ois okc okd oke oki okk oko okr oks oo- ooc ood ooi ook ooo oor oos or- orc ord ore ori ork oro orr ors os- osc osd ose osi osk oso osr oss rcc rcd rce rci rco rcr rcs rdc rdd rde rdi rdo rdr rds re- rec red ree rei rek reo rer res ric rid rie rii rik rio rir ris rkc rke rkk rko rks roc rod roe roi rok roo ror ros rrc rrd rri rrk rrr rrs rsc rsd rse rsi rsk rso rsr rss scc scd sce sci sck sco scr scs sdc sdd sde sdi sdk sdo sdr sds se- sec sed see sei sek seo ser ses sic sid sie sii sik sio sir sis sk- skc skd ske ski skk sko skr sks soc sod soe soi sok soo sor sos sr- src srd sre sri srk sro srr srs ss- ssc ssd sse ssi ssk sso ssr sss