b-tree bbbbbb bebeto bebout beebee beeter berbee berbeo berber bereet berere berour berrer berret bertre berube betere betete betrue bettee better bettor betutu beurre bobber bobete bobote boeber boerre boober booboo bootee booter booue borbor boreto borore bororo borte botere botero botete botoro botree botter boture boubou boueer bouree bourou bourre bouter boutet boutob boutre boutte breere brette bretuo breuer broter brotto brouet brubru bruree brutto bubber bububu burbet burbot burbur burotu burree burrer burret burutu butbro butere butter buttto buutuo ebbert ebbout eburru eebree eototo erbree eroto- errett errour etoeot ettore ettutu euroto eururo eutere euttob oberto obrute obtree obturb oerter oooooo orrour ottoor ouerre out-be outour outreb outter outtro r-tree reboot rebore rebote rebour rebute rerobe reroot reteer reteet reteoo retere retore retort retour retree retret retro- retrot retter rettur retube returu reuere reuour reuter reutte robber robert roboto rooter rootte rorter rotour rotout rotrou rotter roture router routot rubbee rubber rubbot rubout rubro- rubutu rurutu rutour ruttee rutter rutube t-tree t-tube teebee teetee teeter terete terreo terrer terret terror terrot terrou terter tertre tetete tetter tobeor toboot toeout toetoe tooter tootoo torero tororo torret tortor tortou tortue totebo totoro totrot totter toubbe tourbe tourer touret tourou tourte touter toutou toutuo trebor trebur treete tretee trette trotro trotte trueto truett tubber tubboe tuorbe tuotuo turbet turbo- turbot turret turtur tururu tuteur tutour tutter tuttut u-boot u-tube uberto ubetoo ureter urette urouer uroure utero- uteute utroor