bbbbbb booboo bootup borbor bororo botoro boubou bourou boutob brorup brotto brubru brutto bububu burbot burbur burotu burrup burutu butbro buttto buutuo obturb oooooo oporto optoro optout orrour ottoor outour output outrup outtop outtro poboru poopoo pop-up popbot popopo poporo popout poppop poptop pottop poupou pppppp probot propup propur proto- prutot pupput purpur put-up putour putout putput puttoo puttur roboto rootup rotour rotout rotrou routot rub-up rubbot rubout rubro- rubutu ruptor rurutu rutour to-put toboot tootoo top-up toporu topout toppop tororo torpor tortor tortou tot-up totopo totoro totrot tourou toutou toutuo tropo- troppo trotro tuotuo turbo- turbot turtur tururu tutour tuttut u-boot up-put uppoor upprop uproot uruppu utroor