-er bbb bbe bbm bbo bbr be- beb bee bem beo ber bez bmb bme bmm bmo bmr bmz bob boe bom boo bor boz brb bre brm bro brr brz bze bzo bzr bzz ebb ebe ebm ebo ebr eeb eee eem eeo eer em- emb eme emm emo emr eo- eob eoe eom eoo eor erb ere erm ero err erz eze ezo ezr ezz m-o m-r mbb mbe mbm mbo mbr meb mee mem meo mer mez mmb mme mmm mmo mmr mmz mob moe mom moo mor moz mrb mre mrm mro mrr mrz mzb mzm ob- obb obe obm obo obr oeb oee oem oeo oer om- omb ome omm omo omr omz oo- oob oom ooo oor or- orb ore orm oro orr orz oze ozm ozo ozz rbb rbe rbm rbo rbr re- reb ree rem reo rer rez rmb rme rmm rmo rmr rob roe rom roo ror roz rrb rrm rrr rzb rze rzm rzo zbb zbm zbr zeb zee zem zeo zer zez zmb zmm zo- zob zoe zom zoo zor zro zzr zzz