-er ddd dde ddf ddo ddp ddr dds ddt de- ded dee def deo dep der des det dfd dfe dff dfo dfp dfr dfs dft dod doe dof doo dop dor dos dot dpd dpe dpf dpo dpp dpr dps dpt drd dre dro drp drr drs drt dsd dse dsf dso dsp dsr dss dst dtd dte dtf dto dtp dtr dts dtt ed- edd ede edf edo edp edr eds edt eed eee eef eeo eep eer ees eet ef- efd efe eff efo efp efr efs eft eo- eod eoe eof eoo eop eor eos eot ep- epd epe epf epo epp epr eps ept erd ere erf ero erp err ers ert es- esd ese esf eso esp esr ess est etd ete etf eto etp etr ets ett fdd fde fdf fdo fdp fdr fds fdt fed fee fef feo fep fer fes fet ffd ffe fff ffo ffp ffr ffs fft foe fof foo fop for fos fot fpd fpe fpo fpp fpr fps fpt frd fre frf fro frp frr frs frt fsd fse fsf fso fsp fsr fss fst ftd fte ftf fto ftp ftr fts ftt odd ode odf odo odp odr ods odt oed oee oef oeo oep oer oes oet of- ofd ofe off ofo ofp ofr ofs oft oo- ood oof ooo oop oor oos oot op- opd ope opf opo opp opr ops opt or- ord ore orf oro orp orr ors ort os- osd ose osf oso osp osr oss ost ot- otd ote otf oto otp otr ots ott p-p pdd pde pdf pdo pdp pdr pds pdt ped pee pef peo pep per pes pet pfd pfe pff pfo pfp pfr pfs pft pod poe pof poo pop por pos pot ppd ppe ppf ppo ppp ppr pps ppt prd pre prf pro prp prr prs prt ps- psd pse psf pso psp psr pss pst pt- ptd pte ptf pto ptp ptr pts ptt rdd rde rdf rdo rdp rdr rds rdt re- red ree ref reo rep rer res ret rfd rfe rff rfo rfp rfr rfs rft rod roe rof roo rop ror ros rot rpd rpe rpf rpo rpp rpr rps rpt rrd rrf rrp rrr rrs rrt rsd rse rsf rso rsp rsr rss rst rtd rte rtf rto rtp rtr rts rtt sdd sde sdf sdo sdp sdr sds sdt se- sed see sef seo sep ser ses set sfd sfe sff sfo sfp sfr sfs sft sod soe sof soo sop sor sos sot spd spe spf spo spp spr sps spt sr- srd sre srf sro srp srr srs srt ss- ssd sse ssf sso ssp ssr sss sst std ste stf sto stp str sts stt tdd tde tdf tdo tdp tdr tds tdt te- ted tee tef teo tep ter tes tet tfd tfe tff tfo tfp tfr tfs tft to- tod toe tof too top tor tos tot tpd tpe tpf tpo tpp tpr tps tpt trd tre trf tro trp trr trs trt tsd tse tsf tso tsp tsr tss tst ttd tte ttf tto ttp ttr tts ttt