-er a-a a-b a-t aaa aab aad aae aan aar aat aav ab- aba abb abd abe abn abr abt abv ad- ada adb add ade adn adr adt adv aea aeb aed aee aen aer aet aev an- ana anb and ane ann anr ant anv ar- ara arb ard are arn arr art arv at- ata atb atd ate atn atr att atv av- ava avb avd ave avn avr avt baa bab bad bae ban bar bat bav bba bbb bbd bbe bbn bbr bbt bda bdb bdd bde bdr bdt bdv be- bea beb bed bee ben ber bet bev bna bnb bnd bne bnn bnr bnt bnv bra brb brd bre brn brr brt brv bta btb btd bte btn btr btt btv bva bvb bvd bve bvn bvr bvt bvv daa dab dad dae dan dar dat dav dba dbb dbd dbe dbn dbr dbt dbv dda ddb ddd dde ddn ddr ddt de- dea deb ded dee den der det dev dna dnb dnd dne dnn dnr dnt dra drb drd dre drn drr drt drv dta dtb dtd dte dtn dtr dtt dtv dva dvb dvd dve dvn dvr dvt eaa eab ead eae ean ear eat eav eba ebb ebd ebe ebn ebr ebt ebv ed- eda edb edd ede edn edr edt eea eeb eed eee een eer eet eev en- ena enb end ene enn enr ent env era erb erd ere ern err ert erv eta etb etd ete etn etr ett etv eva evb evd eve evn evr evt evv naa nab nad nae nan nar nat nav nba nbb nbd nbe nbn nbr nbt nbv nda ndb ndd nde ndn ndr ndt ndv ne- nea neb ned nee nen ner net nev nna nnb nne nnn nnt nnv nra nrb nrd nre nrn nrr nrt nrv nta ntb ntd nte ntn ntr ntt ntv nva nvb nvd nve nvn nvt nvv ra- raa rab rad rae ran rar rat rav rba rbb rbd rbe rbn rbr rbt rda rdb rdd rde rdn rdr rdt rdv re- rea reb red ree ren rer ret rev rna rnb rnd rnn rnr rnt rnv rra rrb rrd rrn rrr rrt rta rtb rtd rte rtn rtr rtt rtv rva rvb rvd rve rvn rvr rvt rvv taa tab tad tae tan tar tat tav tba tbb tbd tbe tbn tbr tbt tbv tda tdb tdd tde tdn tdr tdt tdv te- tea teb ted tee ten ter tet tev tna tnb tnd tne tnn tnr tnt tra trb trd tre trn trr trt trv tta ttb ttd tte ttn ttr ttt ttv tva tvb tvd tve tvn tvr tvt v-a v-e vaa vab vad vae van var vat vav vba vbd vbr vbv vdb vdd vde vdr vdt vdv vea veb ved vee ven ver vet vn- vna vnd vnr vnv vra vrb vrd vre vrn vrr vrt vta vtb vte vtr vtt vtv vva vvb vvr vvt vvv