-er a-a a-b a-t aaa aab aad aae aao aap aar aas aat ab- aba abb abd abe abo abp abr abs abt ad- ada adb add ade ado adp adr ads adt aea aeb aed aee aeo aep aer aes aet aoa aob aod aoe aoo aop aor aos aot ap- apa apb apd ape apo app apr aps apt ar- ara arb ard are aro arp arr ars art as- asa asb asd ase aso asp asr ass ast at- ata atb atd ate ato atp atr ats att b-p baa bab bad bae bao bap bar bas bat bba bbb bbd bbe bbo bbp bbr bbs bbt bda bdb bdd bde bdo bdp bdr bds bdt be- bea beb bed bee beo bep ber bes bet boa bob bod boe boo bop bor bos bot bpa bpb bpd bpe bpo bpp bpr bps bpt bra brb brd bre bro brp brr brs brt bsa bsb bsd bse bso bsp bsr bss bst bta btb btd bte bto btp btr bts btt daa dab dad dae dao dap dar das dat dba dbb dbd dbe dbo dbp dbr dbs dbt dda ddb ddd dde ddo ddp ddr dds ddt de- dea deb ded dee deo dep der des det doa dob dod doe doo dop dor dos dot dpa dpb dpd dpe dpo dpp dpr dps dpt dra drb drd dre dro drp drr drs drt dsa dsb dsd dse dso dsp dsr dss dst dta dtb dtd dte dto dtp dtr dts dtt eaa eab ead eae eao eap ear eas eat eba ebb ebd ebe ebo ebp ebr ebs ebt ed- eda edb edd ede edo edp edr eds edt eea eeb eed eee eeo eep eer ees eet eo- eoa eob eod eoe eoo eop eor eos eot ep- epa epb epd epe epo epp epr eps ept era erb erd ere ero erp err ers ert es- esa esb esd ese eso esp esr ess est eta etb etd ete eto etp etr ets ett oaa oab oad oae oao oap oar oas oat ob- oba obb obd obe obo obp obr obs obt oda odb odd ode odo odp odr ods odt oea oeb oed oee oeo oep oer oes oet oo- ooa oob ood ooo oop oor oos oot op- opa opb opd ope opo opp opr ops opt or- ora orb ord ore oro orp orr ors ort os- osa osb osd ose oso osp osr oss ost ot- ota otb otd ote oto otp otr ots ott p-p paa pab pad pae pao pap par pas pat pba pbb pbd pbe pbo pbp pbr pbs pbt pda pdb pdd pde pdo pdp pdr pds pdt pea peb ped pee peo pep per pes pet poa pob pod poe poo pop por pos pot ppa ppb ppd ppe ppo ppp ppr pps ppt pra prb prd pre pro prp prr prs prt ps- psa psb psd pse pso psp psr pss pst pt- pta ptb ptd pte pto ptp ptr pts ptt ra- raa rab rad rae rao rap rar ras rat rba rbb rbd rbe rbo rbp rbr rbs rbt rda rdb rdd rde rdo rdp rdr rds rdt re- rea reb red ree reo rep rer res ret roa rob rod roe roo rop ror ros rot rpa rpb rpd rpe rpo rpp rpr rps rpt rra rrb rrd rrp rrr rrs rrt rsa rsb rsd rse rso rsp rsr rss rst rta rtb rtd rte rto rtp rtr rts rtt saa sab sad sae sao sap sar sas sat sba sbb sbd sbe sbo sbp sbr sbs sbt sda sdb sdd sde sdo sdp sdr sds sdt se- sea seb sed see seo sep ser ses set soa sob sod soe soo sop sor sos sot spa spb spd spe spo spp spr sps spt sr- sra srb srd sre sro srp srr srs srt ss- ssa ssb ssd sse sso ssp ssr sss sst sta stb std ste sto stp str sts stt taa tab tad tae tao tap tar tas tat tba tbb tbd tbe tbo tbp tbr tbs tbt tda tdb tdd tde tdo tdp tdr tds tdt te- tea teb ted tee teo tep ter tes tet to- toa tob tod toe too top tor tos tot tpa tpb tpd tpe tpo tpp tpr tps tpt tra trb trd tre tro trp trr trs trt tsa tsb tsd tse tso tsp tsr tss tst tta ttb ttd tte tto ttp ttr tts ttt