-er a-a a-b aaa aab aae aag aaj aak aao aar aas ab- aba abb abe abg abj abk abo abr abs aea aeb aee aeg aej aek aeo aer aes ag- aga agb age agg agj agk ago agr ags aja ajb aje ajj ajk ajo ajr ajs aka akb ake akg akj akk ako akr aks aoa aob aoe aog aoj aok aoo aor aos ar- ara arb are arg arj ark aro arr ars as- asa asb ase asg asj ask aso asr ass baa bab bae bag baj bak bao bar bas bba bbb bbe bbg bbk bbo bbr bbs be- bea beb bee beg bek beo ber bes bga bgb bge bgg bgk bgo bgr bgs bja bjg bjj bjk bjr bjs bka bkb bke bkg bkk bko bkr bks boa bob boe bog boj bok boo bor bos bra brb bre brg brj brk bro brr brs bsa bsb bse bsg bsj bsk bso bsr bss eaa eab eae eag eaj eak eao ear eas eba ebb ebe ebg ebj ebk ebo ebr ebs eea eeb eee eeg eek eeo eer ees ega egb ege egg ego egr egs eja ejo eka ekb eke ekg eko ekr eks eo- eoa eob eoe eog eok eoo eor eos era erb ere erg erk ero err ers es- esa esb ese esg esk eso esr ess gaa gab gae gag gaj gak gao gar gas gba gbe gbg gbj gbk gbo gbr gbs ge- gea geb gee geg gek geo ger ges gga ggb ggg ggj ggo ggr ggs gja gje gjg gjr gka gkb gko gks goa gob goe gog gok goo gor gos gra grb gre grg grj grk gro grr grs gsa gsb gse gsg gsj gsk gso gsr gss jaa jab jae jag jaj jak jao jar jas jba jbg jbj jbk jbo jbr jbs jea jeb jee jeg jej jek jeo jer jes jga jgb jge jgo jgr jgs jja jjb jjg jjj jjk jjr jjs jka jkb jkk jko jkr jks joa job joe jog joj jok joo jor jos jra jrb jrg jrk jro jrr jrs jsa jsb jse jsg jsj jsk jso jsr jss ka- kaa kab kae kag kaj kak kao kar kas kba kbb kbe kbk kbo kbr kbs ke- kea keb kee keg kek keo ker kes kga kgb kgo kgs kjb kje kjr kjs kkb kke kkk kkr kks koa kob koe kog kok koo kor kos kra krg krk kro krr krs ksa ksb kse ksg ksk kso ksr kss oaa oab oae oag oaj oak oao oar oas ob- oba obb obe obg obj obk obo obr obs oea oeb oee oeg oeo oer oes oga oge ogg ogo ogs oja ojb oje ojo ojs oka okb oke okg okj okk oko okr oks oo- ooa oob oog ook ooo oor oos or- ora orb ore org ork oro orr ors os- osa osb ose osg osj osk oso osr oss ra- raa rab rae rag raj rak rao rar ras rba rbb rbe rbg rbk rbo rbr rbs re- rea reb ree reg rek reo rer res rga rgb rge rgg rgk rgo rgr rgs rja rjg rjk rjr rkb rke rkg rkk rko rks roa rob roe rog roj rok roo ror ros rra rrb rrg rrk rrr rrs rsa rsb rse rsg rsj rsk rso rsr rss saa sab sae sag saj sak sao sar sas sba sbb sbe sbg sbj sbk sbo sbr sbs se- sea seb see seg sej sek seo ser ses sga sgb sge sgg sgk sgo sgr sgs sja sjb sje sjj sjk sjr sjs sk- ska skb ske skg skj skk sko skr sks soa sob soe sog soj sok soo sor sos sr- sra srb sre srg srj srk sro srr srs ss- ssa ssb sse ssg ssj ssk sso ssr sss