-er ddd dde ddi ddo ddp ddr dds de- ded dee dei deo dep der des di- did die dii dio dip dir dis dod doe doi doo dop dor dos dpd dpe dpi dpo dpp dpr dps drd dre dri dro drp drr drs dsd dse dsi dso dsp dsr dss ed- edd ede edi edo edp edr eds eed eee eeo eep eer ees eid eie eii eio eip eir eis eo- eod eoe eoi eoo eop eor eos ep- epd epe epi epo epp epr eps erd ere eri ero erp err ers es- esd ese esi eso esp esr ess i-d idd ide idi ido idp idr ids ie- ied iee iei iep ier ies iid iie iii iio iip iir iis io- iod ioe ioi ioo iop ior ios ipd ipe ipi ipo ipp ipr ips ir- ird ire iri iro irp irr irs is- isd ise isi iso isp isr iss o-i odd ode odi odo odp odr ods oed oee oei oeo oep oer oes oid oie oii oio oip oir ois oo- ood ooi ooo oop oor oos op- opd ope opi opo opp opr ops or- ord ore ori oro orp orr ors os- osd ose osi oso osp osr oss p-p pdd pde pdi pdo pdp pdr pds ped pee pei peo pep per pes pid pie pii pio pip pir pis pod poe poi poo pop por pos ppd ppe ppi ppo ppp ppr pps prd pre pri pro prp prr prs ps- psd pse psi pso psp psr pss rdd rde rdi rdo rdp rdr rds re- red ree rei reo rep rer res rid rie rii rio rip rir ris rod roe roi roo rop ror ros rpd rpe rpi rpo rpp rpr rps rrd rri rrp rrr rrs rsd rse rsi rso rsp rsr rss sdd sde sdi sdo sdp sdr sds se- sed see sei seo sep ser ses sid sie sii sio sip sir sis sod soe soi soo sop sor sos spd spe spi spo spp spr sps sr- srd sre sri sro srp srr srs ss- ssd sse ssi sso ssp ssr sss