-er b-p bbb bbe bbm bbo bbp bbr bbt be- beb bee bem beo bep ber bet bmb bme bmm bmo bmp bmr bmt bob boe bom boo bop bor bot bpb bpe bpm bpo bpp bpr bpt brb bre brm bro brp brr brt btb bte btm bto btp btr btt ebb ebe ebm ebo ebp ebr ebt eeb eee eem eeo eep eer eet em- emb eme emm emo emp emr emt eo- eob eoe eom eoo eop eor eot ep- epb epe epm epo epp epr ept erb ere erm ero erp err ert etb ete etm eto etp etr ett m-o m-r mbb mbe mbm mbo mbp mbr mbt meb mee mem meo mep mer met mmb mme mmm mmo mmp mmr mmt mob moe mom moo mop mor mot mpb mpe mpm mpo mpp mpr mpt mrb mre mrm mro mrp mrr mrt mtb mte mtm mto mtp mtr mtt ob- obb obe obm obo obp obr obt oeb oee oem oeo oep oer oet om- omb ome omm omo omp omr omt oo- oob oom ooo oop oor oot op- opb ope opm opo opp opr opt or- orb ore orm oro orp orr ort ot- otb ote otm oto otp otr ott p-p pbb pbe pbm pbo pbp pbr pbt peb pee pem peo pep per pet pmb pme pmm pmo pmp pmr pmt pob poe pom poo pop por pot ppb ppe ppm ppo ppp ppr ppt prb pre prm pro prp prr prt pt- ptb pte ptm pto ptp ptr ptt rbb rbe rbm rbo rbp rbr rbt re- reb ree rem reo rep rer ret rmb rme rmm rmo rmp rmr rmt rob roe rom roo rop ror rot rpb rpe rpm rpo rpp rpr rpt rrb rrm rrp rrr rrt rtb rte rtm rto rtp rtr rtt tbb tbe tbm tbo tbp tbr tbt te- teb tee tem teo tep ter tet tmb tme tmm tmo tmp tmr tmt to- tob toe tom too top tor tot tpb tpe tpm tpo tpp tpr tpt trb tre trm tro trp trr trt ttb tte ttm tto ttp ttr ttt