-er ddd dde ddf ddi ddo ddr dds ddt ddx de- ded dee def dei deo der des det dex dfd dfe dff dfi dfo dfr dfs dft dfx di- did die dif dii dio dir dis dit dix dod doe dof doi doo dor dos dot dox drd dre dri dro drr drs drt drx dsd dse dsf dsi dso dsr dss dst dsx dtd dte dtf dti dto dtr dts dtt dtx dxd dxi dxo dxr dxs dxt dxx ed- edd ede edf edi edo edr eds edt edx eed eee eef eeo eer ees eet eex ef- efd efe eff efi efo efr efs eft efx eid eie eif eii eio eir eis eit eix eo- eod eoe eof eoi eoo eor eos eot erd ere erf eri ero err ers ert es- esd ese esf esi eso esr ess est esx etd ete etf eti eto etr ets ett etx ex- exd exe exi exo exr exs ext exx fdd fde fdf fdi fdo fdr fds fdt fdx fed fee fef fei feo fer fes fet fex ffd ffe fff ffi ffo ffr ffs fft ffx fid fie fif fii fir fis fit fix foe fof foi foo for fos fot fox frd fre frf fri fro frr frs frt fsd fse fsf fsi fso fsr fss fst fsx ftd fte ftf fti fto ftr fts ftt ftx fxe fxi fxr fxs fxt fxx i-d i-f idd ide idf idi ido idr ids idt idx ie- ied iee ief iei ier ies iet iex ifd ife iff ifi ifo ifr ifs ift ifx iid iie iif iii iio iir iis iit iix io- iod ioe iof ioi ioo ior ios iot ir- ird ire irf iri iro irr irs irt irx is- isd ise isf isi iso isr iss ist itd ite itf iti ito its itt itx ixe ixi o-i odd ode odf odi odo odr ods odt oed oee oef oei oeo oer oes oet oex of- ofd ofe off ofi ofo ofr ofs oft ofx oid oie oif oii oio oir ois oit oo- ood oof ooi ooo oor oos oot oox or- ord ore orf ori oro orr ors ort orx os- osd ose osf osi oso osr oss ost osx ot- otd ote otf oti oto otr ots ott ox- oxf oxi oxo oxt oxx rdd rde rdf rdi rdo rdr rds rdt rdx re- red ree ref rei reo rer res ret rex rfd rfe rff rfi rfo rfr rfs rft rid rie rif rii rio rir ris rit rix rod roe rof roi roo ror ros rot rox rrd rrf rri rrr rrs rrt rsd rse rsf rsi rso rsr rss rst rsx rtd rte rtf rti rto rtr rts rtt rtx rxr rxs sdd sde sdf sdi sdo sdr sds sdt se- sed see sef sei seo ser ses set sex sfd sfe sff sfi sfo sfr sfs sft sfx sid sie sif sii sio sir sis sit six sod soe sof soi soo sor sos sot sox sr- srd sre srf sri sro srr srs srt srx ss- ssd sse ssf ssi sso ssr sss sst ssx std ste stf sti sto str sts stt stx sxi sxs sxt t-x tdd tde tdf tdi tdo tdr tds tdt tdx te- ted tee tef tei teo ter tes tet tex tfd tfe tff tfi tfo tfr tfs tft tfx tid tie tif tii tio tir tis tit tix to- tod toe tof toi too tor tos tot tox trd tre trf tri tro trr trs trt trx tsd tse tsf tsi tso tsr tss tst tsx ttd tte ttf tti tto ttr tts ttt ttx txe txf txi txs txt xde xdf xdi xdr xds xdt xed xee xer xes xet xex xfe xfs xft xfx xie xii xio xis xit xix xod xof xoi xoo xor xos xot xox xrd xrf xrt xrx xsi xss xst xtf xti xtr xts xtx xxi xxo xxx