-er a-a a-b a-t aaa aab aad aae aam aar aat ab- aba abb abd abe abm abr abt ad- ada adb add ade adm adr adt aea aeb aed aee aem aer aet ama amb amd ame amm amr amt ar- ara arb ard are arm arr art at- ata atb atd ate atm atr att baa bab bad bae bam bar bat bba bbb bbd bbe bbm bbr bbt bda bdb bdd bde bdm bdr bdt be- bea beb bed bee bem ber bet bma bmb bmd bme bmm bmr bmt bra brb brd bre brm brr brt bta btb btd bte btm btr btt daa dab dad dae dam dar dat dba dbb dbd dbe dbm dbr dbt dda ddb ddd dde ddm ddr ddt de- dea deb ded dee dem der det dma dmb dmd dme dmm dmr dmt dra drb drd dre drm drr drt dta dtb dtd dte dtm dtr dtt eaa eab ead eae eam ear eat eba ebb ebd ebe ebm ebr ebt ed- eda edb edd ede edm edr edt eea eeb eed eee eem eer eet em- ema emb emd eme emm emr emt era erb erd ere erm err ert eta etb etd ete etm etr ett m-r maa mab mad mae mam mar mat mba mbb mbd mbe mbm mbr mbt mda mdb mdd mde mdm mdr mdt mea meb med mee mem mer met mma mmb mmd mme mmm mmr mmt mra mrb mrd mre mrm mrr mrt mta mtb mtd mte mtm mtr mtt ra- raa rab rad rae ram rar rat rba rbb rbd rbe rbm rbr rbt rda rdb rdd rde rdm rdr rdt re- rea reb red ree rem rer ret rma rmb rmd rme rmm rmr rmt rra rrb rrd rrm rrr rrt rta rtb rtd rte rtm rtr rtt taa tab tad tae tam tar tat tba tbb tbd tbe tbm tbr tbt tda tdb tdd tde tdm tdr tdt te- tea teb ted tee tem ter tet tma tmb tmd tme tmm tmr tmt tra trb trd tre trm trr trt tta ttb ttd tte ttm ttr ttt