-er ddd dde ddo ddp ddr ddt de- ded dee deo dep der det dod doe doo dop dor dot dpd dpe dpo dpp dpr dpt drd dre dro drp drr drt dtd dte dto dtp dtr dtt ed- edd ede edo edp edr edt eed eee eeo eep eer eet eo- eod eoe eoo eop eor eot ep- epd epe epo epp epr ept erd ere ero erp err ert etd ete eto etp etr ett odd ode odo odp odr odt oed oee oeo oep oer oet oo- ood ooo oop oor oot op- opd ope opo opp opr opt or- ord ore oro orp orr ort ot- otd ote oto otp otr ott p-p pdd pde pdo pdp pdr pdt ped pee peo pep per pet pod poe poo pop por pot ppd ppe ppo ppp ppr ppt prd pre pro prp prr prt pt- ptd pte pto ptp ptr ptt rdd rde rdo rdp rdr rdt re- red ree reo rep rer ret rod roe roo rop ror rot rpd rpe rpo rpp rpr rpt rrd rrp rrr rrt rtd rte rto rtp rtr rtt tdd tde tdo tdp tdr tdt te- ted tee teo tep ter tet to- tod toe too top tor tot tpd tpe tpo tpp tpr tpt trd tre tro trp trr trt ttd tte tto ttp ttr ttt