-er ddd dde ddo ddp ddr dds ddx de- ded dee deo dep der des dev dex dod doe doo dop dor dos dov dox dpd dpe dpo dpp dpr dps dpv drd dre dro drp drr drs drv drx dsd dse dso dsp dsr dss dsv dsx dvd dve dvp dvr dvs dvx dxd dxo dxp dxr dxs dxx ed- edd ede edo edp edr eds edx eed eee eeo eep eer ees eev eex eo- eod eoe eoo eop eor eos ep- epd epe epo epp epr eps epx erd ere ero erp err ers erv es- esd ese eso esp esr ess esv esx evd eve evo evp evr evs evv ex- exd exe exo exp exr exs exx odd ode odo odp odr ods odv oed oee oeo oep oer oes oex oo- ood ooo oop oor oos oov oox op- opd ope opo opp opr ops opv opx or- ord ore oro orp orr ors orv orx os- osd ose oso osp osr oss osv osx ov- ovd ove ovo ovp ovs ovv ox- oxo oxx p-p pdd pde pdo pdp pdr pds pdv pdx ped pee peo pep per pes pev pex pod poe poo pop por pos pov pox ppd ppe ppo ppp ppr pps ppv ppx prd pre pro prp prr prs prv prx ps- psd pse pso psp psr pss psv psx pvd pve pvo pvp pvr pvs pvv pxe pxr pxs rdd rde rdo rdp rdr rds rdv rdx re- red ree reo rep rer res rev rex rod roe roo rop ror ros rov rox rpd rpe rpo rpp rpr rps rpv rpx rrd rrp rrr rrs rsd rse rso rsp rsr rss rsv rsx rvd rve rvo rvp rvr rvs rvv rxp rxr rxs sdd sde sdo sdp sdr sds sdv se- sed see seo sep ser ses sev sex sod soe soo sop sor sos sov sox spd spe spo spp spr sps spv spx sr- srd sre sro srp srr srs srv srx ss- ssd sse sso ssp ssr sss ssv ssx svd sve svo svp svr svs svv svx sxs v-e vdd vde vdo vdp vdr vds vdv vdx ved vee veo vep ver ves vex vod voe voo vop vor vos vov vox vpd vpe vpo vpp vpr vps vpx vrd vre vrp vrr vrs vsd vse vso vsp vsr vss vsv vvo vvr vvs vvv vxd vxr vxs vxv xde xdr xds xdv xed xee xep xer xes xev xex xod xoo xop xor xos xov xox xpd xpe xpo xpp xps xrd xrx xsp xss xxo xxp xxv xxx