-er -ol b-u bbb bbc bbd bbe bbk bbl bbo bbr bbu bcb bcc bcd bce bck bcl bco bcr bcu bdb bdc bdd bde bdk bdl bdo bdr bdu be- beb bec bed bee bek bel beo ber beu bkb bkc bke bkk bkl bko bkr blb blc bld ble blk bll blo blr blu bob boc bod boe bok bol boo bor bou brb brd bre brk brl bro brr bru bub buc bud bue buk bul buo bur buu c-- cbb cbc cbd cbe cbk cbl cbo cbr cbu ccb ccc ccd cce cck ccl cco ccr ccu cdb cdc cdd cde cdk cdl cdo cdr cdu ce- ceb cec ced cee cek cel ceo cer ceu ckb ckc ckd cko cl- clb clc cld cle clk cll clo clr clu co- cob coc cod coe cok col coo cor cou crb crc crd cre crk crl cro crr cru cub cuc cud cue cuk cul cuo cur cuu dbb dbc dbd dbe dbk dbl dbo dbr dbu dcb dcc dcd dce dck dcl dco dcr dcu ddb ddc ddd dde ddk ddl ddo ddr ddu de- deb dec ded dee dek del deo der deu dkb dkc dke dkk dkl dko dkr dku dl- dlb dlc dld dle dlk dll dlo dlr dlu dob doc dod doe dok dol doo dor dou drb drc drd dre drk drl dro drr dru dub duc dud due duk dul duo dur ebb ebc ebd ebe ebk ebl ebo ebr ebu ec- ecb ecc ecd ece eck ecl eco ecr ecu ed- edb edc edd ede edk edl edo edr edu eeb eec eed eee eek eel eeo eer ekb ekc ekd eke ekl eko ekr eku elb elc eld ele elk ell elo elr elu eo- eob eoc eod eoe eok eol eoo eor eou erb erc erd ere erk erl ero err eru eu- eub euc eud eue eul eur kbb kbc kbd kbe kbk kbl kbo kbr kbu kcb kcc kcd kce kck kcl kcr kcu kdb kdc kde kdk kdl kdo kdr kdu ke- keb kec ked kee kek kel keo ker kkb kkc kke kkk kkl kkr kku kl- klb klc kld klo klr klu kob koc kod koe kok kol koo kor kou krc krd krk krl kro krr kru kub kuc kud kue kuk kul kur kuu lbb lbc lbd lbe lbk lbl lbo lbr lbu lcb lcc lcd lce lck lcl lco lcr lcu ldb ldc ldd lde ldk ldl ldo ldr ldu leb lec led lee lek lel leo ler leu lkb lkl lkr llb llc lld lle llk lll llo llr llu lob loc lod loe lok lol loo lor lou lrb lrc lrd lrk lro lrr lru lub luc lud lue luk lul luo lur luu ob- obb obc obd obe obk obl obo obr obu oc- ocb occ ocd ock ocl oco ocr ocu odb odc odd ode odl odo odr odu oeb oec oed oee oel oeo oer okb okc okd oke okk okl oko okr oku olb olc old ole olk oll olo olu oo- oob ooc ood ook ool ooo oor or- orb orc ord ore ork orl oro orr oru ou- ouc oud oue ouk oul ouo our rbb rbc rbd rbe rbk rbl rbo rbr rbu rcb rcc rcd rce rcl rco rcr rcu rdb rdc rdd rde rdl rdo rdr rdu re- reb rec red ree rek rel reo rer reu rkb rkc rke rkk rko rku rlc rld rle rll rlo rlr rlu rob roc rod roe rok rol roo ror rou rrb rrc rrd rrk rrl rrr rru rub ruc rud rue ruk ruo rur ruu ubb ubc ube ubk ubl ubo ubr ubu ucb ucc ucd uce uck ucl uco ucr ucu udb udc udd ude udk udl udo udr udu ueb uec ued uee uel uer ukb ukc uke ukk ukl ukr uku ulb ulc uld ule ulk ull ulo ulr ulu uob uoc uod uoe uok uol uoo uor ur- urb urc urd ure urk url uro urr uru uuc uue uur uuu