-er b-u bbb bbe bbf bbr bbt bbu be- beb bee bef ber bet beu bfb bfe bff bfr bft bfu brb bre brf brr brt bru btb bte btf btr btt btu bub bue buf bur but buu ebb ebe ebf ebr ebt ebu eeb eee eef eer eet ef- efb efe eff efr eft erb ere erf err ert eru etb ete etf etr ett etu eu- eub eue euf eur eut fbb fbe fbf fbr fbt fbu feb fee fef fer fet feu ffe fff ffr fft ffu frb fre frf frr frt fru ftb fte ftf ftr ftt ftu fub fue fuf fur fut fuu rbb rbe rbf rbr rbt rbu re- reb ree ref rer ret reu rfb rfe rff rfr rft rfu rrb rrf rrr rrt rru rtb rte rtf rtr rtt rtu rub rue ruf rur rut ruu tbb tbe tbf tbr tbt tbu te- teb tee tef ter tet teu tfb tfe tff tfr tft tfu trb tre trf trr trt tru ttb tte ttf ttr ttt ttu tub tue tuf tur tut tuu ubb ube ubf ubr ubt ubu ueb uee uef uer uet ufe uff ufr uft ufu ur- urb ure urf urr urt uru utb ute utf utr utt utu uue uur uut uuu

bbbb bbeb bbet bebb bebe beeb beef beer beet befe beff beft bere berr bert beru bete bett betu beur bftt breb bree bref brer bret brfu brrr brue brut btrt bttb bubb bube bubu buer bueu bufe buff bufr bur- burb bure burr burt buru but- bute butt ebbr eber ebru ebur eeee eefe eete eetu efbr efet eft- eftu erbb erbe ereb erer eret erft erre ertu erub erur etbr etee eter etfb etfe etre ette ettu euer eur- eure eurt feeb feer feet fefe feff ferb fere ferr fert feru fete fetr fett fetu ffee ffff ffrr fftf free fret frub frue fter ftub fubb fubu fuet fuff fufu fur- fure furr furt fute futu rbbb rbbr rebb rebe rebu reeb reef reet refe reff refr reft refu rere rert reru rete retr rett reue reuf reut reuu rfef rrrr rtbf rtee rtfb rubb rube rubu ruer ruet rufe ruff ruft rure ruru rute rutt rutu tbrb tebu teef teer teet teff teft ter- tere terf terr teru tete tetr tett tetu teut tfeb tre- tree tref tret treu trfr trte trtr trub true trut truu ttbb tter ttff tttt tubb tube tubr tubu tuer tuet tufe tuff tuft tufu turb ture turf turr turt turu tute tutt tutu ubbe uber ubet ubtf ufer uffe urbe ure- uret urfe urff urft urre urte urur urut uter uttu uutf uuuu

-tree bbbee be-er beber beebe beeft beete beeut beffe befur berbe beret berre berru berte betee beter betre bett- bette beuer beure beute brebu breef breer breet brere brett breu- brrrr bruer bruet bruff brute btr-t bubbe buber bufet buffe buret burru burte burtt burut buter butte butut ebber ebbet ebert ebure eeeee ef-tu efere efetf effer effet efter efuru efutu erbbe erber erere errtu erte erter etete etree etter eturu eurre febre feere feret ferr- ferre ferte feter fette feuer feute freer freet frere frett freur frute ftrtt fu-fu futur rebbe reber rebet rebut reefe reeft reere refer refet reffe refut rere- reree reret retee reter rette reuer reuet reute rubee ruber ruere ruete ruffe ruter rutte ruutu tbtbt tbutt teber tebet tefe teret tereu terre tert- teter tetr- tette treer treet trefe treff trere trete trett treut trubu truer truff trute ttttt tuber tuffe tufte turbe turbt turet turre turtu turut tutee tutte tuuru uber- ufere urter urubu urutu uter- utter uttur utube uturu uuuuu

b-tree bbbbbb beebee beefer beeter befree befret berbee berber bereet bereft berere berrer berret bertre berube betere betete betrue bettee better betutu beurre breefe breere brette breuer brubru brufut bruree bubber bububu buffer buffet burbet burbur burfee burree burrer burret burutu butere butter ebbert eburru eebree effere effete effutu efreet efter- erbree erfurt errett ettutu eutere ferber ferfer ferrer ferret ferrur fertee ferter fetter feture feuter frefre frette freure fterer fterre fuerte furber furfur furrer furrfu futret futter future r-tree rebuff rebute reefer reeffe refeet refeff refert refete refret refter refurb refute reteer reteet retere retree retret retter rettur retube returf returu reuere reuter reutte rubbee rubber rubutu rufete ruffer ruffet rufter rurutu ruttee rutter rutube t-tree t-tube teebee teetee teeter terbuf terete terrer terret terter tertre tetete tetter trebur treete trefet trefte tretee trette truett trufte tubber tuffet tufter turbet turfer turret turtur tururu tuteur tutter tuttut u-tube ufreet ureter urette uruffe uteute

bbbbbbb be-free bebeeru beetree berbere berefet berrett bertree brebeuf brutter buffett burbure burette ferebee ferrere ferrure freebee freeter fretter frubber furrure futerer futureu referee referer refrete refuter rerefer reteere reterre retrete rettert reutter tebbutt terere terreer terrere tettete treetee trettre truebut turbett tut-tut ub-tree utterer

bbbbbbbb bebetter bebutter bee-butt befetter berebere betterer bruterer bubertre buffeter bur-tree buruburu etbetter ferreter ferrette fetterer feuterer freebeer rebuffer rebuffet rebutter referree referrer teruteru treefree treffurt

beebeebee butterbur ettubrute ruff-tree tebe-tebe teuf-teuf tuff-tuff

berberburr betterbeer buffetbuff butterbeer ferretfeet rubbertree

ettutubrute ueberreuter

buffetbuffet

bbbbbbbbbbbbbbb