-er -ol bbb bbc bbd bbe bbk bbl bbo bbr bcb bcc bcd bce bck bcl bco bcr bdb bdc bdd bde bdk bdl bdo bdr be- beb bec bed bee bek bel beo ber bkb bkc bke bkk bkl bko bkr blb blc bld ble blk bll blo blr bob boc bod boe bok bol boo bor brb brd bre brk brl bro brr c-- cbb cbc cbd cbe cbk cbl cbo cbr ccb ccc ccd cce cck ccl cco ccr cdb cdc cdd cde cdk cdl cdo cdr ce- ceb cec ced cee cek cel ceo cer ckb ckc ckd cko cl- clb clc cld cle clk cll clo clr co- cob coc cod coe cok col coo cor crb crc crd cre crk crl cro crr dbb dbc dbd dbe dbk dbl dbo dbr dcb dcc dcd dce dck dcl dco dcr ddb ddc ddd dde ddk ddl ddo ddr de- deb dec ded dee dek del deo der dkb dkc dke dkk dkl dko dkr dl- dlb dlc dld dle dlk dll dlo dlr dob doc dod doe dok dol doo dor drb drc drd dre drk drl dro drr ebb ebc ebd ebe ebk ebl ebo ebr ec- ecb ecc ecd ece eck ecl eco ecr ed- edb edc edd ede edk edl edo edr eeb eec eed eee eek eel eeo eer ekb ekc ekd eke ekl eko ekr elb elc eld ele elk ell elo elr eo- eob eoc eod eoe eok eol eoo eor erb erc erd ere erk erl ero err kbb kbc kbd kbe kbk kbl kbo kbr kcb kcc kcd kce kck kcl kcr kdb kdc kde kdk kdl kdo kdr ke- keb kec ked kee kek kel keo ker kkb kkc kke kkk kkl kkr kl- klb klc kld klo klr kob koc kod koe kok kol koo kor krc krd krk krl kro krr lbb lbc lbd lbe lbk lbl lbo lbr lcb lcc lcd lce lck lcl lco lcr ldb ldc ldd lde ldk ldl ldo ldr leb lec led lee lek lel leo ler lkb lkl lkr llb llc lld lle llk lll llo llr lob loc lod loe lok lol loo lor lrb lrc lrd lrk lro lrr ob- obb obc obd obe obk obl obo obr oc- ocb occ ocd ock ocl oco ocr odb odc odd ode odl odo odr oeb oec oed oee oel oeo oer okb okc okd oke okk okl oko okr olb olc old ole olk oll olo oo- oob ooc ood ook ool ooo oor or- orb orc ord ore ork orl oro orr rbb rbc rbd rbe rbk rbl rbo rbr rcb rcc rcd rce rcl rco rcr rdb rdc rdd rde rdl rdo rdr re- reb rec red ree rek rel reo rer rkb rkc rke rkk rko rlc rld rle rll rlo rlr rob roc rod roe rok rol roo ror rrb rrc rrd rrk rrl rrr