-er bbb bbe bbg bbo bbr bbs be- beb bee beg beo ber bes bez bgb bge bgg bgo bgr bgs bgz bob boe bog boo bor bos boz brb bre brg bro brr brs brz bsb bse bsg bso bsr bss bze bzo bzr bzs bzz ebb ebe ebg ebo ebr ebs eeb eee eeg eeo eer ees egb ege egg ego egr egs eo- eob eoe eog eoo eor eos erb ere erg ero err ers erz es- esb ese esg eso esr ess eze ezo ezr ezs ezz gbe gbg gbo gbr gbs gbz ge- geb gee geg geo ger ges gez ggb ggg ggo ggr ggs ggz gob goe gog goo gor gos goz grb gre grg gro grr grs gsb gse gsg gso gsr gss gzo gzr ob- obb obe obg obo obr obs oeb oee oeg oeo oer oes oge ogg ogo ogs oo- oob oog ooo oor oos or- orb ore org oro orr ors orz os- osb ose osg oso osr oss oze ozo ozs ozz rbb rbe rbg rbo rbr rbs re- reb ree reg reo rer res rez rgb rge rgg rgo rgr rgs rob roe rog roo ror ros roz rrb rrg rrr rrs rsb rse rsg rso rsr rss rzb rze rzo sbb sbe sbg sbo sbr sbs se- seb see seg seo ser ses sez sgb sge sgg sgo sgr sgs sob soe sog soo sor sos soz sr- srb sre srg sro srr srs ss- ssb sse ssg sso ssr sss ssz sze szr z-g zbb zbr zbs zeb zee zeo zer zes zez zgb zgg zgs zo- zob zoe zog zoo zor zos zro zrs zse zsg zsz zzr zzs zzz