-er bbb bbe bbm bbr bbt be- beb bee bem ber bet bmb bme bmm bmr bmt brb bre brm brr brt btb bte btm btr btt ebb ebe ebm ebr ebt eeb eee eem eer eet em- emb eme emm emr emt erb ere erm err ert etb ete etm etr ett m-r mbb mbe mbm mbr mbt meb mee mem mer met mmb mme mmm mmr mmt mrb mre mrm mrr mrt mtb mte mtm mtr mtt rbb rbe rbm rbr rbt re- reb ree rem rer ret rmb rme rmm rmr rmt rrb rrm rrr rrt rtb rte rtm rtr rtt tbb tbe tbm tbr tbt te- teb tee tem ter tet tmb tme tmm tmr tmt trb tre trm trr trt ttb tte ttm ttr ttt