-er bbb bbe bbi bbr bbs bbt be- beb bee bei ber bes bet bez bi- bib bie bii bir bis bit biz brb bre bri brr brs brt brz bsb bse bsi bsr bss bst btb bte bti btr bts btt btz bze bzr bzs bzz ebb ebe ebi ebr ebs ebt eeb eee eer ees eet eib eie eii eir eis eit erb ere eri err ers ert erz es- esb ese esi esr ess est etb ete eti etr ets ett etz eze ezr ezs ezz ibb ibe ibi ibr ibs ibt ibz ie- iee iei ier ies iet iib iie iii iir iis iit ir- irb ire iri irr irs irt is- isb ise isi isr iss ist itb ite iti its itt itz ize izi izz rbb rbe rbi rbr rbs rbt re- reb ree rei rer res ret rez rib rie rii rir ris rit riz rrb rri rrr rrs rrt rsb rse rsi rsr rss rst rtb rte rti rtr rts rtt rtz rzb rze sbb sbe sbi sbr sbs sbt se- seb see sei ser ses set sez sib sie sii sir sis sit sr- srb sre sri srr srs srt ss- ssb sse ssi ssr sss sst ssz stb ste sti str sts stt stz sze szi szr tbb tbe tbi tbr tbs tbt tbz te- teb tee tei ter tes tet tez tib tie tii tir tis tit tiz trb tre tri trr trs trt trz tsb tse tsi tsr tss tst ttb tte tti ttr tts ttt tze tzs zbb zbr zbs zbt zeb zee zer zes zet zez zib zie zir zis zit ziz zrs zse zsi zst zsz zte ztr zzr zzs zzt zzz