-er -ic bbb bbc bbd bbe bbi bbk bbo bbr bcb bcc bcd bce bci bck bco bcr bdb bdc bdd bde bdi bdk bdo bdr be- beb bec bed bee bei bek beo ber bi- bib bic bid bie bii bik bio bir bkb bkc bke bkk bko bkr bob boc bod boe boi bok boo bor brb brd bre bri brk bro brr c-- cbb cbc cbd cbe cbi cbk cbo cbr ccb ccc ccd cce cci cck cco ccr cdb cdc cdd cde cdi cdk cdo cdr ce- ceb cec ced cee cei cek ceo cer ci- cib cic cid cie cii cik cio cir ckb ckc ckd cki cko co- cob coc cod coe coi cok coo cor crb crc crd cre cri crk cro crr dbb dbc dbd dbe dbi dbk dbo dbr dcb dcc dcd dce dci dck dco dcr ddb ddc ddd dde ddi ddk ddo ddr de- deb dec ded dee dei dek deo der di- dib dic did die dii dik dio dir dkb dkc dke dki dkk dko dkr dob doc dod doe doi dok doo dor drb drc drd dre dri drk dro drr ebb ebc ebd ebe ebi ebk ebo ebr ec- ecb ecc ecd ece eci eck eco ecr ed- edb edc edd ede edi edk edo edr eeb eec eed eee eek eeo eer eib eic eid eie eii eik eio eir ekb ekc ekd eke eki eko ekr eo- eob eoc eod eoe eoi eok eoo eor erb erc erd ere eri erk ero err i-d ibb ibc ibd ibe ibi ibk ibo ibr icb icc icd ice ici ick ico icr idb idc idd ide idi idk ido idr ie- iec ied iee iei iek ier iib iic iid iie iii iio iir ikb ikc ike iki ikk iko ikr io- iob ioc iod ioe ioi ioo ior ir- irb irc ird ire iri irk iro irr kbb kbc kbd kbe kbi kbk kbo kbr kcb kcc kcd kce kci kck kcr kdb kdc kde kdk kdo kdr ke- keb kec ked kee kei kek keo ker kib kic kid kie kii kik kio kir kkb kkc kke kki kkk kkr kob koc kod koe koi kok koo kor krc krd kri krk kro krr o-i ob- obb obc obd obe obi obk obo obr oc- ocb occ ocd oci ock oco ocr odb odc odd ode odi odo odr oeb oec oed oee oei oeo oer oib oic oid oie oii oik oio oir okb okc okd oke oki okk oko okr oo- oob ooc ood ooi ook ooo oor or- orb orc ord ore ori ork oro orr rbb rbc rbd rbe rbi rbk rbo rbr rcb rcc rcd rce rci rco rcr rdb rdc rdd rde rdi rdo rdr re- reb rec red ree rei rek reo rer rib ric rid rie rii rik rio rir rkb rkc rke rkk rko rob roc rod roe roi rok roo ror rrb rrc rrd rri rrk rrr