-er bbb bbe bbi bbk bbo bbr bbs bbt be- beb bee bei bek beo ber bes bet bez bi- bib bie bii bik bio bir bis bit biz bkb bke bkk bko bkr bks bkt bob boe boi bok boo bor bos bot boz brb bre bri brk bro brr brs brt brz bsb bse bsi bsk bso bsr bss bst btb bte bti btk bto btr bts btt btz bze bzo bzr bzs bzz ebb ebe ebi ebk ebo ebr ebs ebt eeb eee eek eeo eer ees eet eib eie eii eik eio eir eis eit ekb eke eki eko ekr eks ekt eo- eob eoe eoi eok eoo eor eos eot erb ere eri erk ero err ers ert erz es- esb ese esi esk eso esr ess est etb ete eti etk eto etr ets ett etz eze ezo ezr ezs ezz ibb ibe ibi ibk ibo ibr ibs ibt ibz ie- iee iei iek ier ies iet iib iie iii iio iir iis iit ikb ike iki ikk iko ikr iks ikt io- iob ioe ioi ioo ior ios iot ir- irb ire iri irk iro irr irs irt is- isb ise isi isk iso isr iss ist itb ite iti itk ito its itt itz ize izi izo izz k-t k-z kbb kbe kbi kbk kbo kbr kbs kbz ke- keb kee kei kek keo ker kes ket kez kib kie kii kik kio kir kis kit kiz kkb kke kki kkk kkr kks kkt kob koe koi kok koo kor kos kot koz kri krk kro krr krs krt ksb kse ksi ksk kso ksr kss kst ktb kte ktk kto ktr kts ktt kzo o-i ob- obb obe obi obk obo obr obs obt oeb oee oei oeo oer oes oet oib oie oii oik oio oir ois oit oiz okb oke oki okk oko okr oks oo- oob ooi ook ooo oor oos oot or- orb ore ori ork oro orr ors ort orz os- osb ose osi osk oso osr oss ost ot- otb ote oti otk oto otr ots ott otz oze ozo ozs ozt ozz rbb rbe rbi rbk rbo rbr rbs rbt re- reb ree rei rek reo rer res ret rez rib rie rii rik rio rir ris rit riz rkb rke rkk rko rks rkt rkz rob roe roi rok roo ror ros rot roz rrb rri rrk rrr rrs rrt rsb rse rsi rsk rso rsr rss rst rtb rte rti rtk rto rtr rts rtt rtz rzb rze rzo sbb sbe sbi sbk sbo sbr sbs sbt se- seb see sei sek seo ser ses set sez sib sie sii sik sio sir sis sit sk- skb ske ski skk sko skr sks skt sob soe soi sok soo sor sos sot soz sr- srb sre sri srk sro srr srs srt ss- ssb sse ssi ssk sso ssr sss sst ssz stb ste sti stk sto str sts stt stz sze szi szr tbb tbe tbi tbk tbo tbr tbs tbt tbz te- teb tee tei tek teo ter tes tet tez tib tie tii tik tio tir tis tit tiz tkb tke tkk tko tkr tks tkt tkz to- tob toe toi tok too tor tos tot toz trb tre tri trk tro trr trs trt trz tsb tse tsi tsk tso tsr tss tst ttb tte tti ttk tto ttr tts ttt tze tzs zbb zbr zbs zbt zeb zee zek zeo zer zes zet zez zib zie zik zio zir zis zit ziz zks zo- zob zoe zoi zok zoo zor zos zot zro zrs zse zsi zst zsz zte ztr zzr zzs zzt zzz