-er a-a a-b a-i a-t aaa aab aad aae aai aao aar aas aat ab- aba abb abd abe abi abo abr abs abt ad- ada adb add ade adi ado adr ads adt aea aeb aed aee aei aeo aer aes aet ai- aia aib aid aie aii aio air ais ait aoa aob aod aoe aoi aoo aor aos aot ar- ara arb ard are ari aro arr ars art as- asa asb asd ase asi aso asr ass ast at- ata atb atd ate ati ato atr ats att baa bab bad bae bai bao bar bas bat bba bbb bbd bbe bbi bbo bbr bbs bbt bda bdb bdd bde bdi bdo bdr bds bdt be- bea beb bed bee bei beo ber bes bet bi- bia bib bid bie bii bio bir bis bit boa bob bod boe boi boo bor bos bot bra brb brd bre bri bro brr brs brt bsa bsb bsd bse bsi bso bsr bss bst bta btb btd bte bti bto btr bts btt daa dab dad dae dai dao dar das dat dba dbb dbd dbe dbi dbo dbr dbs dbt dda ddb ddd dde ddi ddo ddr dds ddt de- dea deb ded dee dei deo der des det di- dia dib did die dii dio dir dis dit doa dob dod doe doi doo dor dos dot dra drb drd dre dri dro drr drs drt dsa dsb dsd dse dsi dso dsr dss dst dta dtb dtd dte dti dto dtr dts dtt eaa eab ead eae eai eao ear eas eat eba ebb ebd ebe ebi ebo ebr ebs ebt ed- eda edb edd ede edi edo edr eds edt eea eeb eed eee eeo eer ees eet eia eib eid eie eii eio eir eis eit eo- eoa eob eod eoe eoi eoo eor eos eot era erb erd ere eri ero err ers ert es- esa esb esd ese esi eso esr ess est eta etb etd ete eti eto etr ets ett i-d ia- iaa iab iad iae iai iao iar ias iat iba ibb ibd ibe ibi ibo ibr ibs ibt ida idb idd ide idi ido idr ids idt ie- iea ied iee iei ier ies iet iia iib iid iie iii iio iir iis iit io- ioa iob iod ioe ioi ioo ior ios iot ir- ira irb ird ire iri iro irr irs irt is- isa isb isd ise isi iso isr iss ist ita itb itd ite iti ito its itt o-i oaa oab oad oae oai oao oar oas oat ob- oba obb obd obe obi obo obr obs obt oda odb odd ode odi odo odr ods odt oea oeb oed oee oei oeo oer oes oet oia oib oid oie oii oio oir ois oit oo- ooa oob ood ooi ooo oor oos oot or- ora orb ord ore ori oro orr ors ort os- osa osb osd ose osi oso osr oss ost ot- ota otb otd ote oti oto otr ots ott ra- raa rab rad rae rai rao rar ras rat rba rbb rbd rbe rbi rbo rbr rbs rbt rda rdb rdd rde rdi rdo rdr rds rdt re- rea reb red ree rei reo rer res ret ria rib rid rie rii rio rir ris rit roa rob rod roe roi roo ror ros rot rra rrb rrd rri rrr rrs rrt rsa rsb rsd rse rsi rso rsr rss rst rta rtb rtd rte rti rto rtr rts rtt saa sab sad sae sai sao sar sas sat sba sbb sbd sbe sbi sbo sbr sbs sbt sda sdb sdd sde sdi sdo sdr sds sdt se- sea seb sed see sei seo ser ses set sia sib sid sie sii sio sir sis sit soa sob sod soe soi soo sor sos sot sr- sra srb srd sre sri sro srr srs srt ss- ssa ssb ssd sse ssi sso ssr sss sst sta stb std ste sti sto str sts stt taa tab tad tae tai tao tar tas tat tba tbb tbd tbe tbi tbo tbr tbs tbt tda tdb tdd tde tdi tdo tdr tds tdt te- tea teb ted tee tei teo ter tes tet tia tib tid tie tii tio tir tis tit to- toa tob tod toe toi too tor tos tot tra trb trd tre tri tro trr trs trt tsa tsb tsd tse tsi tso tsr tss tst tta ttb ttd tte tti tto ttr tts ttt