-er b-u bbb bbe bbm bbr bbt bbu be- beb bee bem ber bet beu bez bmb bme bmm bmr bmt bmu bmz brb bre brm brr brt bru brz btb bte btm btr btt btu btz bub bue bum bur but buu buz bze bzr bzu bzz ebb ebe ebm ebr ebt ebu eeb eee eem eer eet em- emb eme emm emr emt emu erb ere erm err ert eru erz etb ete etm etr ett etu etz eu- eub eue eur eut eze ezr ezz m-r mbb mbe mbm mbr mbt mbu meb mee mem mer met meu mez mmb mme mmm mmr mmt mmu mmz mrb mre mrm mrr mrt mru mrz mtb mte mtm mtr mtt mtu mub mue mum mur mut muu mzb mzm mzt rbb rbe rbm rbr rbt rbu re- reb ree rem rer ret reu rez rmb rme rmm rmr rmt rrb rrm rrr rrt rru rtb rte rtm rtr rtt rtu rtz rub rue rum rur rut ruu ruz rzb rze rzm tbb tbe tbm tbr tbt tbu tbz te- teb tee tem ter tet teu tez tmb tme tmm tmr tmt tmu tmz trb tre trm trr trt tru trz ttb tte ttm ttr ttt ttu tub tue tum tur tut tuu tuz tze tzu ubb ube ubr ubt ubu ueb uee uem uer uet um- umb ume umm umr umt umu ur- urb ure urm urr urt uru urz utb ute utm utr utt utu utz uue uum uur uut uuu uzb uzu zbb zbm zbr zbt zeb zee zem zer zet zez zmb zmm zmt zte ztm ztr zub zum zur zut zuz zzr zzt zzz

bbbb bbeb bbet bebb bebe beeb beem beer beet beme bemu bere berm berr bert beru bete bett betu betz beur beze bezu breb bree brem brer bret brez brrm brrr brue brum brut bruz btrt bttb bubb bube bubu buem buer bueu bum- bumb bur- burb bure burm burr burt buru burz but- bute butt butz buuz buze buzz bzer bzzt bzzz ebbr eber ebru ebur eeee eete eetu eeze embe embr emer emet emeu emme emmu emre emte erbb erbe ereb erem erer eret erez erme erre ertu ertz erub erum erur etbr etee etem eter etre etrm ette ettu etuz euer eur- eure eurt ezem ezer ezuz mebe meem meer meet meez meme memr memu memz mer- merb mere merm mert meru merz met- mete mett metu metz meum meze mezz mmmm mrbb mrbm mreb mree mrtm mrtt mtre mtrr mttr mube muee muet mume mumm mumu mure murr murt muru mute mutt mutu muut muze muzz mze mzee rbbb rbbr rebb rebe rebu reeb reem reet reme rere rert reru rete retr rett retz reue reut reuu reze rezu rmtu rrrr rrum rtee rubb rube rubu ruer ruet ruez rumb rume rumm rumt rure ruru rute rutt rutu ruze tbrb tebu teem teer teet teez teme temu ter- tere term terr teru tete tetr tett tetu tetz teut tezu tezz tmbr tmtt tre- tree trem tret treu trez trmb trmu trte trtr trub true trut truu ttbb tter tttt tubb tube tubr tubu tuer tuet tumb tume tumu turb ture turm turr turt turu tute tutt tutu tuum tuzu tuzz tzum tzur tzut tzzt ubbe uber ubet uetz umb- umbe umer umet umut urbe ure- uret urre urte urum urur urut uruz uter utmb uttu uuuu uzeb uzer zber zebe zebu zeme zert zete zeze zmeu zmub zrze zubr zubu zurb zurr zuru zuzu zzzz

-tree bbbee be-er beber beebe beete beeut beez bembe bemer bemet berbe beret berme berre berru berte berum berze betee beter betre bett- bette beuer beure beute bezer brebu breem breer breet breme bremm brere brett bretz breu- breze brmmm brrrr bruer bruet brume brumm brute bruzz btr-t bubbe buber bumbu bumme buret burru burte burtt burut buter butme butte butut buzet buzzr bzzzt ebber ebbet ebert ebure eeeee embee ember embue emeer emere emert emmer emmet emtee emure erbbe erber erem- erere eretz errtu erte erter etete etree etter eturu eum-u eurre euzet mbebe mbere mbret mbube mburu mebbe meemu meere meete membe memer merer meret merez merre merte mertz merur meter metr- metre mette metur metze meuer meure meute meuze mezez mezre mezze mmmmm mreru mrmet mt-te mt-tm mt-tr mt-tt mtree mtume mumbe mumme mummu muret mureu murre murru murtz murum murut murz muter mutet mutum mutze muzur mzuzu rebbe reber rebet rebut reeme reere reetz reeze remee remer remet remue rere- reree reret rerez rerum retee retem reter rette reuer reuet reume reute reuze rmutt rubee ruber ruere ruete ruetz rumbe rumer rummu ruter rutte ruutu tbtbt tbutt teber tebet teeme teemu tembe tembu terem teret tereu terme terre tert- teter tetr- tette treer treet treme trere trete trett treut trubu truer trume trute ttttt tuber tumbe tumbu tumut turbe turbt turem turet turre turtu turut turze tutee tutte tuuru tzere tzute uber- ubrez ubume uetze umbe- umber umbre umeer umeme umezu ureme urmuz urter urubu urutu urzut uter- utmer utrum utter uttur utube uturu uuuuu uzere z-ter zbure zebre zebub zemer zerbe zerre zerum zeuet zmutt zrbtt zterm zu-zu zuber zzzzz

b-tree bbbbbb beebee beebem beembe beemer beerme beerze beeter beezer bemeet bemete bemute berbee berber bereet berere bermet berrer berret bertem bertre berube beteem betere betete betrue bettee better betutu betzet beumer beurre bezmer breere breeze bremer brette breuer brubru bruree brutum brzuze bubber bububu bumbee bummer burbet burbur burree burrer burret burutu burzet burzum butere butter butzer buzzer ebbert eburru eburum eebree embree embrue embute emeere emeter emeute emmert emmett emmure erbree eretum errett etrez ettutu eutere m-tree mbembe meerut meeter meetme meetre member membre mememe memere merete meretz mermer mermet merrem merret merter merure meteer metrer metrum metter mettet mettur metzer meurte muerte muette mummer murmur murree murter mutere mutter muttur mutuum muumuu muzeum r-tree rebute remeet remete remeue reteer reteet retere reterm retree retret retter rettur retube returu reuere reuter reutte reutum rubbee rubber