-er bbb bbe bbg bbi bbo bbr bbs bbt bbx be- beb bee beg bei beo ber bes bet bex bgb bge bgg bgi bgo bgr bgs bgt bgx bi- bib bie big bii bio bir bis bit bix bob boe bog boi boo bor bos bot box brb bre brg bri bro brr brs brt brx bsb bse bsg bsi bso bsr bss bst bsx btb bte btg bti bto btr bts btt btx bxb bxi bxo bxx ebb ebe ebg ebi ebo ebr ebs ebt ebx eeb eee eeg eeo eer ees eet eex egb ege egg egi ego egr egs egt egx eib eie eig eii eio eir eis eit eix eo- eob eoe eog eoi eoo eor eos eot erb ere erg eri ero err ers ert es- esb ese esg esi eso esr ess est esx etb ete etg eti eto etr ets ett etx ex- exe exi exo exr exs ext exx gbe gbg gbi gbo gbr gbs gbt gbx ge- geb gee geg gei geo ger ges get gex ggb ggg ggi ggo ggr ggs ggt gib gie gig gii gio gir gis git gob goe gog goi goo gor gos got gox grb gre grg gri gro grr grs grt grx gsb gse gsg gsi gso gsr gss gst gsx gtb gte gtg gti gto gtr gts gtt gtx gxs gxt ibb ibe ibg ibi ibo ibr ibs ibt ibx ie- iee ieg iei ier ies iet iex igb ige igg igi igo igr igs igt iib iie iii iio iir iis iit iix io- iob ioe iog ioi ioo ior ios iot ir- irb ire irg iri iro irr irs irt irx is- isb ise isg isi iso isr iss ist itb ite itg iti ito its itt itx ixe ixi o-i ob- obb obe obg obi obo obr obs obt obx oeb oee oeg oei oeo oer oes oet oex oge ogg ogi ogo ogs ogt ogx oib oie oii oio oir ois oit oo- oob oog ooi ooo oor oos oot oox or- orb ore org ori oro orr ors ort orx os- osb ose osg osi oso osr oss ost osx ot- otb ote otg oti oto otr ots ott ox- oxb oxi oxo oxt oxx rbb rbe rbg rbi rbo rbr rbs rbt rbx re- reb ree reg rei reo rer res ret rex rgb rge rgg rgi rgo rgr rgs rgt rgx rib rie rig rii rio rir ris rit rix rob roe rog roi roo ror ros rot rox rrb rrg rri rrr rrs rrt rsb rse rsg rsi rso rsr rss rst rsx rtb rte rtg rti rto rtr rts rtt rtx rxr rxs sbb sbe sbg sbi sbo sbr sbs sbt sbx se- seb see seg sei seo ser ses set sex sgb sge sgg sgi sgo sgr sgs sgt sgx sib sie sig sii sio sir sis sit six sob soe sog soi soo sor sos sot sox sr- srb sre srg sri sro srr srs srt srx ss- ssb sse ssg ssi sso ssr sss sst ssx stb ste stg sti sto str sts stt stx sxi sxs sxt t-x tbb tbe tbg tbi tbo tbr tbs tbt te- teb tee teg tei teo ter tes tet tex tgb tge tgg tgi tgo tgr tgs tgt tib tie tig tii tio tir tis tit tix to- tob toe tog toi too tor tos tot tox trb tre trg tri tro trr trs trt trx tsb tse tsg tsi tso tsr tss tst tsx ttb tte ttg tti tto ttr tts ttt ttx txe txi txs txt xbe xbr xbx xee xeg xer xes xet xex xge xgi xie xii xio xis xit xix xog xoi xoo xor xos xot xox xrt xrx xsb xsi xss xst xti xtr xts xtx xxi xxo xxx