-er bbb bbe bbi bbk bbr bbt be- beb bee bei bek ber bet bi- bib bie bii bik bir bit bkb bke bkk bkr bkt brb bre bri brk brr brt btb bte bti btk btr btt ebb ebe ebi ebk ebr ebt eeb eee eek eer eet eib eie eii eik eir eit ekb eke eki ekr ekt erb ere eri erk err ert etb ete eti etk etr ett ibb ibe ibi ibk ibr ibt ie- iee iei iek ier iet iib iie iii iir iit ikb ike iki ikk ikr ikt ir- irb ire iri irk irr irt itb ite iti itk itt k-t kbb kbe kbi kbk kbr ke- keb kee kei kek ker ket kib kie kii kik kir kit kkb kke kki kkk kkr kkt kri krk krr krt ktb kte ktk ktr ktt rbb rbe rbi rbk rbr rbt re- reb ree rei rek rer ret rib rie rii rik rir rit rkb rke rkk rkt rrb rri rrk rrr rrt rtb rte rti rtk rtr rtt tbb tbe tbi tbk tbr tbt te- teb tee tei tek ter tet tib tie tii tik tir tit tkb tke tkk tkr tkt trb tre tri trk trr trt ttb tte tti ttk ttr ttt

bbbb bbeb bbet bebb bebe bebi beeb beek beer beet beik beir beit beke beki bere beri berk berr bert bete beti bett bibb bibe bibi bieb bier biet bike birb bire biri birk birr birt bite bitt breb bree brei brek brer bret brie brik brit brkb brrr btek btie btrt bttb ebbr eber ebit eeee eeke eete eiei eier eike eiki eire eitb eiti eitr ekeb ekek eker eket ekki erbb erbe ereb erei erer eret erie erik erit erke erki erre etbr etee eter etik etre ette etti i-be ibet ibie ibri ibtb ieet ieie iere ieri iett iiie iiii iiit iitr iitt ikee iker ikki ikri irbe iree irer iri- irie irki irre irri irte irti itbe itek iter itet itie itri kbbb kbbe kbbi kbbk kbbr kbbt kbeb kbee kbek kber kbet kbib kbie kbik kbit kbkb kbkk kbkr kbrb kbre kbri kbrk kbrt kbtb kbte kbtk kbtr kbtt kebb kebe kebi kebr kebt keek keer keet keib keii keik keir kekb keke keki ker- kerb kere keri kerk kerr kert ket- kete keti ketk ketr kett kibb kibe kibi kibr kibt kier kiii kiik kiit kiki kikk kikr kikt kirb kiri kirk kirr kirt kite kiti kitr kitt kkbb kkbe kkbi kkbr kkbt kkik kkit kkkk kkrb kkre kkrk kkrr kkrt kktk krbb krbe krbi krbk krbr krbt kreb kree krei krek kret krib krik krit krke krki krkk krkr krrb krre krri krrk krrr krrt krti krtk krtr ktbb ktbr ktbt ktee ktek ktib ktie ktik ktkb ktke ktkk ktkr ktkt ktrb ktre ktri ktrk ktrr ktrt ktti kttk kttr kttt rbbb rbbr rebb rebe rebk reeb reek reet reii reik reir reit reke reki rekt rere reri rert rete reti retr rett rib- ribe riek rier riet rike riki rikk rire riri rite riti ritt rrrr rtee rtei tbit tbrb teek teer teet teie teir teke ter- tere teri terk terr tete teti tetr tett tibi tie- tiee tiei tier tiet tiit tike tiki tirb tire tiri tirr tite titi titt tre- tree trei trek tret tri- trib trie trik trit trte trtr ttbb tter tttt

-tree b-r-k bbbee be-er bebek beber bebti beebe beeke beeri beete beibi beier beire beite beker bekir bekke bekti berbe berei berek beret berie berit berk- berke berre berri berte berti betee beter betie betke betre bett- bette betti bibbe biber bibie bibri biebe bieke biere bieri biert bieti biker bikie birie bitek biter bitit bitki bitte bitti bkite breek breer breet breik breit breke brere brett bribe brier brike brite britt brrrr btr-t ebber ebbet ebbie ebert ebibe ebike eeeee eerie eerik eetti eiker eirie eiter eitri ekbir ekker erbbe erber erere erier erite erkki erte erter eteke etete etike etite etree etrek etter ettie i-bet i-rtk ibert ibeti ibrik iebet ieiri ierei iette iiiee iiiii iitti ikbke ikire irbit irete iriki irite irker irrit itbit itete itire itter ittre ittti k-t-b kebbe kebek keber kebir keere keeri keiki keire keiri keitt kekri kerei kerek keret kerie kerik kerre kerri ketek keter ketib kette ketti kibbe kibbi kibei kibet kibi- kieke kiiki kikki kirie kirke kirki kirre kitee kiter kitir kitki kitte kitti kreek kreke kreki krete kribi kriek krier krike kriti rebbe reber rebet rebit reere reeti reiek reike reiki rekke rere- reree reret rerik rerir retee reter retie retki rette ribbi riber ribet ribie rieti rikei riker rikki ririe ritek rt-rk tbeti tbtbt teber tebet tebi- teiki teket tekir tekke tekki tekti terek teret terki terre terri tert- teter tetr- tetri tette ti-ti tibbi tiber tibet tieit tieke tiere tieri tikei tiket tikit tikki tikri tiree tirer tiret tirit titer titii titik titre titte titti tkiet tkirk treer treet treib treie treit trere treri trete trett tribe trieb triei trier triet trike triki trikk trit- trite tritt ttttt

b-tree bbbbbb bebite beebee beeker beeter beiber bekker berbee berber bereet bereke berere berker berrer berret berrie bertie bertre betere betete betire bettee better bettie bettik bibber bibiri bibrik bieber bikker biribi birket birkie biteit bitier bitter bittie breere breite brekke brette bribe- bribee briber bribir bribri brikke e-bike ebbert ebr-ii ebrie eebree eerier eibert erbree erebti errett i-bere i-bete i-tree ikette ikkeri irrite ittiri k-tree kebber kebbie kebrit keeker keerie keerti keiter kerber kereki kerite kerker kerrie kerrik kertee ketiki ketter kettie kettik kibbee kibber kibbie kibrit kieber kiekie kierie kikiki kikkik kiriri kirite kiriti kirker kirtik kiteer kitere kittib kittie kreeri kreker kretek kritik r-tree rebbit rebite reeker reiber reikie reiter rekrei reteer reteet retere retire retree retret retter ribber ribbet ribbie ribbit ribibe ribier rieber rieker rieter riette rietti rititi ritter t-tree tebbit teebee teetee teeter teikei teirei tekbir tereki terete teribe terrer terret terrie territ terter tertre tetete tetter tibbit