-er ddd dde ddm ddo ddr dds ddt de- ded dee dem deo der des det dmd dme dmm dmo dmr dms dmt dod doe dom doo dor dos dot drd dre drm dro drr drs drt dsd dse dsm dso dsr dss dst dtd dte dtm dto dtr dts dtt ed- edd ede edm edo edr eds edt eed eee eem eeo eer ees eet em- emd eme emm emo emr ems emt eo- eod eoe eom eoo eor eos eot erd ere erm ero err ers ert es- esd ese esm eso esr ess est etd ete etm eto etr ets ett m-o m-r mdd mde mdm mdo mdr mds mdt med mee mem meo mer mes met mmd mme mmm mmo mmr mms mmt mod moe mom moo mor mos mot mrd mre mrm mro mrr mrs mrt msd mse msm mso msr mss mst mtd mte mtm mto mtr mts mtt odd ode odm odo odr ods odt oed oee oem oeo oer oes oet om- omd ome omm omo omr oms omt oo- ood oom ooo oor oos oot or- ord ore orm oro orr ors ort os- osd ose osm oso osr oss ost ot- otd ote otm oto otr ots ott rdd rde rdm rdo rdr rds rdt re- red ree rem reo rer res ret rmd rme rmm rmo rmr rms rmt rod roe rom roo ror ros rot rrd rrm rrr rrs rrt rsd rse rsm rso rsr rss rst rtd rte rtm rto rtr rts rtt sdd sde sdm sdo sdr sds sdt se- sed see sem seo ser ses set smd sme smm smo smr sms smt sod soe som soo sor sos sot sr- srd sre srm sro srr srs srt ss- ssd sse ssm sso ssr sss sst std ste stm sto str sts stt tdd tde tdm tdo tdr tds tdt te- ted tee tem teo ter tes tet tmd tme tmm tmo tmr tms tmt to- tod toe tom too tor tos tot trd tre trm tro trr trs trt tsd tse tsm tso tsr tss tst ttd tte ttm tto ttr tts ttt