bbbb bbeb bbet bebb bebe bebo beeb beek beer beet beke beko beo- beok beor beot bere berk bero berr bert bete beto bett bobb bobe bobo boee boeo boer boet boke boko boob booe book boor boot bor- bore bork boro borr bort botb bote boto bott breb bree brek breo brer bret brkb brob broe brok broo bror brot brrr btek btob btor btrt bttb ebbo ebbr eber eboe eboo ebor ebro eeee eeke eero eete ekeb ekek eker eket eore eoto erbb erbe ereb erer eret erke erob eroe eroo erre erro etbr etee eter etoe etok etre etro ette etto kbbb kbbe kbbk kbbo kbbr kbbt kbeb kbee kbek kbeo kber kbet kbkb kbkk kbko kbkr kbob kboe kbok kboo kbot kbrb kbre kbrk kbro kbrt kbtb kbte kbtk kbto kbtr kbtt kebb kebe kebr kebt keek keer keet kekb keke keko keok ker- kerb kere kerk kero kerr kert ket- kete ketk keto ketr kett kkbb kkbe kkbo kkbr kkbt kkkk kkob kkoo kkor kkot kkrb kkre kkrk kkro kkrr kkrt kktk kobb kobe kobk kobo kobr kokb koke kokk koko kokr koob kook kooo koor koot korb kore kork koro korr kort kotb kote kotk koto kotr kott krbb krbe krbk krbr krbt kreb kree krek kreo kret krke krkk krko krkr krob kroe krok kroo kror krrb krre krrk krro krrr krrt krtk krto krtr ktbb ktbr ktbt ktee ktek ktkb ktke ktkk ktko ktkr ktkt ktob ktoe ktok ktoo ktor ktot ktrb ktre ktrk ktro ktrr ktrt kttk ktto kttr kttt o-eo obbo ober obet obkb oboe obok obor obot obre obro oere oker oket okko okok okor okot okre okro okto oobe ooer oooo oore oort ootb orbb orbe orbo ore- oreb orek oreo orer orke orko oro- oroe orok oror orot orro orte orto otee oter oto- otoe otok otoo otor otre otro otte otto rbbb rbbr rebb rebe rebk rebo reeb reek reet reke reko rekt reot rere rero rert rete reto retr rett rob- robb robe robo robt roer roet roke rokk roko rokr roob rook roor root rore rork roro rort rote rotk roto rotr rott rrrr rtee tbrb tebo teek teer teet teke teok teor ter- tere terk tero terr tete teto tetr tett tobe tobo tobt toee toek toer toet toke toko took toor toot tore tork toro torr tort tote toto totr tott tre- tree trek treo tret troe troo trot trte trtr ttbb tteo tter ttoe tttt