-tree eeeee ef-tu efere efetf effer effet efrem efter efuru efutu emeer emere emert emmer emmet emtee emure erem- erere errtu erte erter etete etree etter eturu eum-u eurre feeme feere femme femur feret ferme ferr- ferre ferte feter fette feuer feute freer freet freme fremm frere frett freur frume frute ftrtt fu-fu fumee fumer fumet furme futur meefe meemu meere meete memer merer meret merre merte merur meter metr- metre mette metur meuer meure meute mmmmm mreru mrmet mt-te mt-tf mt-tm mt-tr mt-tt mterf mtfmt mtree mtume muffe mumme mummu muret mureu murre murru murum murut muter mutet mutum reefe reeft reeme reere refer refet reffe refme refut remee remer remet remue remuf rere- reree reret rerum retee retem reter rette reuer reuet reume reute rmutt rtrfm ruere ruete ruffe rumer rummu ruter rutte ruutu teeme teemu tefe terem teret tereu terme terre tert- teter tetr- tette treer treet trefe treff treme trere trete trett treut truer truff trume trute ttttt tuffe tufte tumut turem turet turre turtu turut tutee tutte tuuru ufere umeer umeme ureme urter urutu uter- utmer utrum utter uttur uturu uuuuu