-er a-a a-b a-t aaa aab aae aag aao aar aat aau ab- aba abb abe abg abo abr abt abu aea aeb aee aeg aeo aer aet aeu ag- aga agb age agg ago agr agt agu aoa aob aoe aog aoo aor aot aou ar- ara arb are arg aro arr art aru at- ata atb ate atg ato atr att atu au- aua aub aue aug auo aur aut b-u baa bab bae bag bao bar bat bau bba bbb bbe bbg bbo bbr bbt bbu be- bea beb bee beg beo ber bet beu bga bgb bge bgg bgo bgr bgt bgu boa bob boe bog boo bor bot bou bra brb bre brg bro brr brt bru bta btb bte btg bto btr btt btu bua bub bue bug buo bur but buu eaa eab eae eag eao ear eat eau eba ebb ebe ebg ebo ebr ebt ebu eea eeb eee eeg eeo eer eet ega egb ege egg ego egr egt egu eo- eoa eob eoe eog eoo eor eot eou era erb ere erg ero err ert eru eta etb ete etg eto etr ett etu eu- eua eub eue eug eur eut gaa gab gae gag gao gar gat gau gba gbe gbg gbo gbr gbt gbu ge- gea geb gee geg geo ger get geu gga ggb ggg ggo ggr ggt ggu goa gob goe gog goo gor got gou gra grb gre grg gro grr grt gru gta gtb gte gtg gto gtr gtt gtu gu- gua gub gue gug guo gur gut guu oaa oab oae oag oao oar oat oau ob- oba obb obe obg obo obr obt obu oea oeb oee oeg oeo oer oet oga oge ogg ogo ogt oo- ooa oob oog ooo oor oot or- ora orb ore org oro orr ort oru ot- ota otb ote otg oto otr ott otu ou- oua oue ouo our out ra- raa rab rae rag rao rar rat rau rba rbb rbe rbg rbo rbr rbt rbu re- rea reb ree reg reo rer ret reu rga rgb rge rgg rgo rgr rgt roa rob roe rog roo ror rot rou rra rrb rrg rrr rrt rru rta rtb rte rtg rto rtr rtt rtu rua rub rue rug ruo rur rut ruu taa tab tae tag tao tar tat tau tba tbb tbe tbg tbo tbr tbt tbu te- tea teb tee teg teo ter tet teu tga tgb tge tgg tgo tgr tgt tgu to- toa tob toe tog too tor tot tou tra trb tre trg tro trr trt tru tta ttb tte ttg tto ttr ttt ttu tua tub tue tug tuo tur tut tuu ua- uaa uab uae uag uao uar uat uau uba ubb ube ubg ubo ubr ubt ubu uea ueb uee ueg uer uet uga ugb uge ugg ugo ugr ugt ugu uoa uob uoe uog uoo uor uot ur- ura urb ure urg uro urr urt uru uta utb ute uto utr utt utu uua uue uug uur uut uuu