-er b-u bbb bbd bbe bbo bbr bbt bbu bdb bdd bde bdo bdr bdt bdu be- beb bed bee beo ber bet beu bob bod boe boo bor bot bou brb brd bre bro brr brt bru btb btd bte bto btr btt btu bub bud bue buo bur but buu dbb dbd dbe dbo dbr dbt dbu ddb ddd dde ddo ddr ddt ddu de- deb ded dee deo der det deu dob dod doe doo dor dot dou drb drd dre dro drr drt dru dtb dtd dte dto dtr dtt dtu dub dud due duo dur dut ebb ebd ebe ebo ebr ebt ebu ed- edb edd ede edo edr edt edu eeb eed eee eeo eer eet eo- eob eod eoe eoo eor eot eou erb erd ere ero err ert eru etb etd ete eto etr ett etu eu- eub eud eue eur eut ob- obb obd obe obo obr obt obu odb odd ode odo odr odt odu oeb oed oee oeo oer oet oo- oob ood ooo oor oot or- orb ord ore oro orr ort oru ot- otb otd ote oto otr ott otu ou- oud oue ouo our out rbb rbd rbe rbo rbr rbt rbu rdb rdd rde rdo rdr rdt rdu re- reb red ree reo rer ret reu rob rod roe roo ror rot rou rrb rrd rrr rrt rru rtb rtd rte rto rtr rtt rtu rub rud rue ruo rur rut ruu tbb tbd tbe tbo tbr tbt tbu tdb tdd tde tdo tdr tdt tdu te- teb ted tee teo ter tet teu to- tob tod toe too tor tot tou trb trd tre tro trr trt tru ttb ttd tte tto ttr ttt ttu tub tud tue tuo tur tut tuu ubb ube ubo ubr ubt ubu udb udd ude udo udr udt udu ueb ued uee uer uet uob uod uoe uoo uor uot ur- urb urd ure uro urr urt uru utb utd ute uto utr utt utu uue uur uut uuu

bbbb bbdd bbdo bbeb bbet bd-r bebb bebe bebo bede bedo bedu beeb beed beer beet beo- beod beor beot berd bere bero berr bert beru bete beto bett betu beur bobb bobe bobo bobu bodb bode bodo bodu boee boeo boer boet boob bood booe boor boot bor- bord bore boro borr bort boru botb botd bote boto bott boud boue bour bout brdo brdt breb bred bree breo brer bret brob brod broe broo bror brot brou brrr brud brue brut btdt btob btor btrt bttb bubb bube bubo bubu budb budd bude budo budu buer bueu bur- burb burd bure buro burr burt buru but- bute buto butt d-bo dbtt dddd ddot ddre ddub debe debt debu dedd dede dedo dedu deeb deed deer deet deor der- derb dere dero derr dete deto detr deue deur deut dobb dobe dobu dod- dodd dode dodo doer doob dood door doot dord dore doro dorr dort doru dotd dote doto dott doub doud doue dour dout dred dree dret drob drod drot drou drub drue drut druu dted dtor dtot dub- dubb dube dubu dudd dude dudo dudu duer duet duo- dure duro durt duru dute duur duut ebbo ebbr ebed eber eboe eboo ebor ebro ebru ebur edde eddo ede- eder edod edou edru edur eede eedu eeee eero eete eetu eode eore eotd eoto erbb erbe erde ereb ered erer eret erob erod eroe eroo erre erro ertu erub erur etbr etee eter etoe etre etro ette etto ettu eude euer eur- eure euro eurt o-eo obbo obdt obed ober obet oboe obor obot obre obro obtd odbo oddd oded odeo oder odet odoo odor odot odou odtu odur oedo oere oobe ooer oooo oord oore oort ootb orbb orbe orbo orbu orde ordo ordu ore- oreb ored oreo orer oro- oroe oror orot orro orte orto orub otbd oted otee oter oto- otoe otoo otor otre otro otte otto ottu otur oude oued ouer our- oure ouro ourt out- outb oute outo ouu- rbbb rbbr rder rebb rebe rebo rebu redd rede redo redr redu reeb reed reet reod reot reou rerd rere rero rert reru retd rete reto retr rett reue reut reuu rob- robb robe robo robt robu rodd rode rodo roed roer roet roob rood roor root rore roro rort roru rote roto rotr rott roub roud roue rout rred rrrr rtdt rtee rubb rube rubu rudd rude rudo rued ruer ruet rurd rure ruro ruru rute ruto rutt rutu ruud tbrb tddb tdor tebo tebu tedd tede teed teer teet teor ter- tere tero terr teru tete teto tetr tett tetu teut tobe tobo tobt tobu todd tode todo todt todu toed toee toer toet tood toor toot tord tore toro torr tort toru totd tote toto totr tott tour tout tre- tred tree treo tret treu trod troe troo trot trou trte trtr trub trud true trut truu ttbb tteo tter ttoe tttt tubb tube tubo tubr tubu tude tudu tuer tuet tuor turb turd ture turo turr turt turu tute tuto tutt tutu tuuo ubbe ubbo uber ubet ubod ubud uder udet udoo udot uor- uore urbe urde urdu ure- ured uret uro- uroo urre urte urur urut uter utor utto uttu uuuu

-tree b-e-d bbbee bd-re bdoor bdort be-er be-ro bebdo bebed beber bebod bebot bedde bedee beder bedet bedot bedub bedue beebe beede beerd beete beeut beode beord beote beour berbe berde berdu bered beret berob beroe beror berre berru berte berto betee beter betoo betor betou betre bett- bette betto beuer beure beute bo-bo bobet bobr bobre bodd- boded boder bodoe bodor boedo boero boeur boode booed booer boord boore boort booru borbo borde bordo bored boree borer boret boro- borod boroo borot borou borre borro borut botet botou botro botte bottu boudu boued bouee bouer bouet bourd boure boute bouto brebu bredd brede bredt breed breer breet breo- brerd brere breto brett breu- brobo brodd