-er a-a a-b aaa aab aae aag aam aao aar aas ab- aba abb abe abg abm abo abr abs aea aeb aee aeg aem aeo aer aes ag- aga agb age agg agm ago agr ags ama amb ame amg amm amo amr ams aoa aob aoe aog aom aoo aor aos ar- ara arb are arg arm aro arr ars as- asa asb ase asg asm aso asr ass baa bab bae bag bam bao bar bas bba bbb bbe bbg bbm bbo bbr bbs be- bea beb bee beg bem beo ber bes bga bgb bge bgg bgm bgo bgr bgs bma bmb bme bmg bmm bmo bmr bms boa bob boe bog bom boo bor bos bra brb bre brg brm bro brr brs bsa bsb bse bsg bsm bso bsr bss eaa eab eae eag eam eao ear eas eba ebb ebe ebg ebm ebo ebr ebs eea eeb eee eeg eem eeo eer ees ega egb ege egg egm ego egr egs em- ema emb eme emg emm emo emr ems eo- eoa eob eoe eog eom eoo eor eos era erb ere erg erm ero err ers es- esa esb ese esg esm eso esr ess gaa gab gae gag gam gao gar gas gba gbe gbg gbm gbo gbr gbs ge- gea geb gee geg gem geo ger ges gga ggb ggg ggm ggo ggr ggs gma gmb gme gmg gmm gmo gmr gms goa gob goe gog gom goo gor gos gra grb gre grg grm gro grr grs gsa gsb gse gsg gsm gso gsr gss m-o m-r maa mab mae mag mam mao mar mas mba mbb mbe mbg mbm mbo mbr mbs mea meb mee meg mem meo mer mes mga mgb mge mgm mgo mgr mgs mma mmb mme mmg mmm mmo mmr mms moa mob moe mog mom moo mor mos mra mrb mre mrg mrm mro mrr mrs msa msb mse msg msm mso msr mss oaa oab oae oag oam oao oar oas ob- oba obb obe obg obm obo obr obs oea oeb oee oeg oem oeo oer oes oga oge ogg ogo ogs om- oma omb ome omg omm omo omr oms oo- ooa oob oog oom ooo oor oos or- ora orb ore org orm oro orr ors os- osa osb ose osg osm oso osr oss ra- raa rab rae rag ram rao rar ras rba rbb rbe rbg rbm rbo rbr rbs re- rea reb ree reg rem reo rer res rga rgb rge rgg rgo rgr rgs rma rmb rme rmg rmm rmo rmr rms roa rob roe rog rom roo ror ros rra rrb rrg rrm rrr rrs rsa rsb rse rsg rsm rso rsr rss saa sab sae sag sam sao sar sas sba sbb sbe sbg sbm sbo sbr sbs se- sea seb see seg sem seo ser ses sga sgb sge sgg sgm sgo sgr sgs sma smb sme smg smm smo smr sms soa sob soe sog som soo sor sos sr- sra srb sre srg srm sro srr srs ss- ssa ssb sse ssg ssm sso ssr sss