-er b-p bbb bbd bbe bbo bbp bbr bbt bdb bdd bde bdo bdp bdr bdt be- beb bed bee beo bep ber bet bob bod boe boo bop bor bot bpb bpd bpe bpo bpp bpr bpt brb brd bre bro brp brr brt btb btd bte bto btp btr btt dbb dbd dbe dbo dbp dbr dbt ddb ddd dde ddo ddp ddr ddt de- deb ded dee deo dep der det dob dod doe doo dop dor dot dpb dpd dpe dpo dpp dpr dpt drb drd dre dro drp drr drt dtb dtd dte dto dtp dtr dtt ebb ebd ebe ebo ebp ebr ebt ed- edb edd ede edo edp edr edt eeb eed eee eeo eep eer eet eo- eob eod eoe eoo eop eor eot ep- epb epd epe epo epp epr ept erb erd ere ero erp err ert etb etd ete eto etp etr ett ob- obb obd obe obo obp obr obt odb odd ode odo odp odr odt oeb oed oee oeo oep oer oet oo- oob ood ooo oop oor oot op- opb opd ope opo opp opr opt or- orb ord ore oro orp orr ort ot- otb otd ote oto otp otr ott p-p pbb pbd pbe pbo pbp pbr pbt pdb pdd pde pdo pdp pdr pdt peb ped pee peo pep per pet pob pod poe poo pop por pot ppb ppd ppe ppo ppp ppr ppt prb prd pre pro prp prr prt pt- ptb ptd pte pto ptp ptr ptt rbb rbd rbe rbo rbp rbr rbt rdb rdd rde rdo rdp rdr rdt re- reb red ree reo rep rer ret rob rod roe roo rop ror rot rpb rpd rpe rpo rpp rpr rpt rrb rrd rrp rrr rrt rtb rtd rte rto rtp rtr rtt tbb tbd tbe tbo tbp tbr tbt tdb tdd tde tdo tdp tdr tdt te- teb ted tee teo tep ter tet to- tob tod toe too top tor tot tpb tpd tpe tpo tpp tpr tpt trb trd tre tro trp trr trt ttb ttd tte tto ttp ttr ttt