-er ddd dde ddm ddr dds ddt de- ded dee dem der des det dmd dme dmm dmr dms dmt drd dre drm drr drs drt dsd dse dsm dsr dss dst dtd dte dtm dtr dts dtt ed- edd ede edm edr eds edt eed eee eem eer ees eet em- emd eme emm emr ems emt erd ere erm err ers ert es- esd ese esm esr ess est etd ete etm etr ets ett m-r mdd mde mdm mdr mds mdt med mee mem mer mes met mmd mme mmm mmr mms mmt mrd mre mrm mrr mrs mrt msd mse msm msr mss mst mtd mte mtm mtr mts mtt rdd rde rdm rdr rds rdt re- red ree rem rer res ret rmd rme rmm rmr rms rmt rrd rrm rrr rrs rrt rsd rse rsm rsr rss rst rtd rte rtm rtr rts rtt sdd sde sdm sdr sds sdt se- sed see sem ser ses set smd sme smm smr sms smt sr- srd sre srm srr srs srt ss- ssd sse ssm ssr sss sst std ste stm str sts stt tdd tde tdm tdr tds tdt te- ted tee tem ter tes tet tmd tme tmm tmr tms tmt trd tre trm trr trs trt tsd tse tsm tsr tss tst ttd tte ttm ttr tts ttt