-er ddd dde ddf ddl ddr dds ddt de- ded dee def del der des det dfd dfe dff dfl dfr dfs dft dl- dld dle dlf dll dlr dls dlt drd dre drl drr drs drt dsd dse dsf dsl dsr dss dst dtd dte dtf dtl dtr dts dtt ed- edd ede edf edl edr eds edt eed eee eef eel eer ees eet ef- efd efe eff efl efr efs eft eld ele elf ell elr els elt erd ere erf erl err ers ert es- esd ese esf esl esr ess est etd ete etf etl etr ets ett fdd fde fdf fdl fdr fds fdt fed fee fef fel fer fes fet ffd ffe fff ffl ffr ffs fft fld fle flf fll flr fls flt frd fre frf frl frr frs frt fsd fse fsf fsl fsr fss fst ftd fte ftf ftl ftr fts ftt ldd lde ldf ldl ldr lds ldt led lee lef lel ler les let lfd lfe lff lfl lfr lfs lft lld lle llf lll llr lls llt lrd lrf lrr lrs lrt lsd lse lsf lsl lsr lss lst ltd lte ltf ltl ltr lts ltt rdd rde rdf rdl rdr rds rdt re- red ree ref rel rer res ret rfd rfe rff rfl rfr rfs rft rld rle rlf rll rlr rls rlt rrd rrf rrl rrr rrs rrt rsd rse rsf rsl rsr rss rst rtd rte rtf rtl rtr rts rtt sdd sde sdf sdl sdr sds sdt se- sed see sef sel ser ses set sfd sfe sff sfl sfr sfs sft sld sle slf sll slr sls slt sr- srd sre srf srl srr srs srt ss- ssd sse ssf ssl ssr sss sst std ste stf stl str sts stt tdd tde tdf tdl tdr tds tdt te- ted tee tef tel ter tes tet tfd tfe tff tfl tfr tfs tft tld tle tlf tll tlr tls tlt trd tre trf trl trr trs trt tsd tse tsf tsl tsr tss tst ttd tte ttf ttl ttr tts ttt