-er ddd dde ddi ddk ddo ddp ddr dds de- ded dee dei dek deo dep der des dev di- did die dii dik dio dip dir dis div dke dki dkk dko dkp dkr dks dod doe doi dok doo dop dor dos dov dpd dpe dpi dpk dpo dpp dpr dps dpv drd dre dri drk dro drp drr drs drv dsd dse dsi dsk dso dsp dsr dss dsv dvd dve dvi dvk dvp dvr dvs ed- edd ede edi edk edo edp edr eds eed eee eek eeo eep eer ees eev eid eie eii eik eio eip eir eis eiv ekd eke eki eko ekp ekr eks ekv eo- eod eoe eoi eok eoo eop eor eos ep- epd epe epi epo epp epr eps erd ere eri erk ero erp err ers erv es- esd ese esi esk eso esp esr ess esv evd eve evi evo evp evr evs evv i-d i-v idd ide idi idk ido idp idr ids idv ie- ied iee iei iek iep ier ies iev iid iie iii iio iip iir iis ike iki ikk iko ikr iks ikv io- iod ioe ioi ioo iop ior ios iov ipd ipe ipi ipo ipp ipr ips ipv ir- ird ire iri irk iro irp irr irs irv is- isd ise isi isk iso isp isr iss isv ivd ive ivi ivo ivp ivr ivs ivv kde kdk kdo kdp kdr kds ke- ked kee kei kek keo kep ker kes kev kid kie kii kik kio kip kir kis kiv kke kki kkk kkp kkr kks kkv kod koe koi kok koo kop kor kos kpd kpe kpi kpk kpo kpp kpr kps kpv krd kri krk kro krp krr krs krv ksd kse ksi ksk kso ksp ksr kss ksv kvi kvk kvo kvp kvr kvs kvv o-i odd ode odi odo odp odr ods odv oed oee oei oeo oep oer oes oid oie oii oik oio oip oir ois oiv okd oke oki okk oko okp okr oks oo- ood ooi ook ooo oop oor oos oov op- opd ope opi opk opo opp opr ops opv or- ord ore ori ork oro orp orr ors orv os- osd ose osi osk oso osp osr oss osv ov- ovd ove ovi ovo ovp ovs ovv p-p pdd pde pdi pdk pdo pdp pdr pds pdv ped pee pei pek peo pep per pes pev pid pie pii pik pio pip pir pis piv pkd pke pki pko pkp pkr pks pod poe poi pok poo pop por pos pov ppd ppe ppi ppk ppo ppp ppr pps ppv prd pre pri prk pro prp prr prs prv ps- psd pse psi psk pso psp psr pss psv pvd pve pvi pvk pvo pvp pvr pvs pvv rdd rde rdi rdo rdp rdr rds rdv re- red ree rei rek reo rep rer res rev rid rie rii rik rio rip rir ris riv rke rkk rko rkp rks rkv rod roe roi rok roo rop ror ros rov rpd rpe rpi rpk rpo rpp rpr rps rpv rrd rri rrk rrp rrr rrs rsd rse rsi rsk rso rsp rsr rss rsv rvd rve rvi rvo rvp rvr rvs rvv sdd sde sdi sdk sdo sdp sdr sds sdv se- sed see sei sek seo sep ser ses sev sid sie sii sik sio sip sir sis siv sk- skd ske ski skk sko skp skr sks sod soe soi sok soo sop sor sos sov spd spe spi spk spo spp spr sps spv sr- srd sre sri srk sro srp srr srs srv ss- ssd sse ssi ssk sso ssp ssr sss ssv svd sve svi svk svo svp svr svs svv v-e vdd vde vdi vdk vdo vdp vdr vds vdv ved vee vei vek veo vep ver ves vi- vid vie vii vik vio vip vir vis viv vkp vod voe voi vok voo vop vor vos vov vpd vpe vpi vpk vpo vpp vpr vps vrd vre vri vrk vrp vrr vrs vsd vse vsi vsk vso vsp vsr vss vsv vvi vvo vvr vvs vvv