-tree eeeee ef-tu efere efetf effer effet efore efter efuru efutu eofor eorre erere eroor erore eroto error errtu erte erter etete etoro etour etree etter eturu euro- eurre feeor feere fefor feoff feret ferr- ferre ferro ferte feter feto- fetor fette feuer feute foore foote fore- foreo foret forro forte forto forur fotte fotur fouee fouet foure fouro freer freet frere frett freur froot frore frote frute fruto ftrtt fu-fu fuero furo- furor futur o-fer offer offof offre offto ofoto ofour ofter oo-er ooooo oreo- orere orero orfeo orfeu orfoe orfor oroer orout orret orter ortet ortoo oruro orutu otere otero ototo otour otter ottur oture ouert ouoro oure- outer outof outre outro outto reefe reeft reere refer refet reffe reffo refut rere- reree reret retee reter retro rette retto reuer reuet reute ro-ro roero roffe rofor rooer roofe rooft roore roote rooue rorer roter roto- rotor rotot rotte rotto rouer rouet roufe roure route routt ruere ruete ruffe ruffo rufo- ruter rutte ruutu tefe teret tereu teror terre terro tert- teruo teter tetr- tetro tette teuto toeof toerr toeto tofet toffo tofor tofte toore toreo toret torre torro torte torto tortu torue toter toto- totoe totoo totte toure touro toute treer treet trefe treff trere trete trett treut troee trofe troff troft trott troue trout truer truff truro trute ttttt tuero tuffe tufte tuotu turet turot turre turro turtu turut tutee tuteo tutor tutte tutto tuuru ufere ufofu uouee ureo- urour urter urutu uter- utero utro- utror utter uttur uturu ututo uuuuu