-er -ic bbb bbc bbe bbi bbr bbs bbt bcb bcc bce bci bcr bcs bct be- beb bec bee bei ber bes bet bi- bib bic bie bii bir bis bit brb bre bri brr brs brt bsb bsc bse bsi bsr bss bst btb btc bte bti btr bts btt c-- cbb cbc cbe cbi cbr cbs cbt ccb ccc cce cci ccr ccs cct ce- ceb cec cee cei cer ces cet ci- cib cic cie cii cir cis cit crb crc cre cri crr crs crt csb csc cse csi csr css cst ctb ctc cte cti ctr cts ctt ebb ebc ebe ebi ebr ebs ebt ec- ecb ecc ece eci ecr ecs ect eeb eec eee eer ees eet eib eic eie eii eir eis eit erb erc ere eri err ers ert es- esb esc ese esi esr ess est etb etc ete eti etr ets ett ibb ibc ibe ibi ibr ibs ibt icb icc ice ici icr ics ict ie- iec iee iei ier ies iet iib iic iie iii iir iis iit ir- irb irc ire iri irr irs irt is- isb isc ise isi isr iss ist itb itc ite iti its itt rbb rbc rbe rbi rbr rbs rbt rcb rcc rce rci rcr rcs rct re- reb rec ree rei rer res ret rib ric rie rii rir ris rit rrb rrc rri rrr rrs rrt rsb rsc rse rsi rsr rss rst rtb rtc rte rti rtr rts rtt sbb sbc sbe sbi sbr sbs sbt scb scc sce sci scr scs sct se- seb sec see sei ser ses set sib sic sie sii sir sis sit sr- srb src sre sri srr srs srt ss- ssb ssc sse ssi ssr sss sst stb stc ste sti str sts stt tbb tbc tbe tbi tbr tbs tbt tcb tcc tce tci tcr tcs tct te- teb tec tee tei ter tes tet tib tic tie tii tir tis tit trb trc tre tri trr trs trt tsb tsc tse tsi tsr tss tst ttb ttc tte tti ttr tts ttt