-tree c-tec ccccc ccett ceere cefcu cerc- cerce cerec cerer ceret cerre certe cette cfu-e crece creer creft crete cretu creu- creue cruce cruet crufe cruft crure ctree cttee cufeu cuffe cufre curce curer curet curre cutcu cutee cuter ectfe eeeee ef-tu efere efetf effer effet efter efuru efutu erect erere errtu erte erter eruct etete etree etter eturu eucre eurre feere ferce feret ferr- ferre ferte feter fette feuer feute freer freet frere frett freur fruct frute ftrtt fu-fu futur recce recet rect- recte recue recur recut reece reefe reeft reere refer refet reffe refut rere- reree reret retee reter rette reuer reuet reute rucer ruere ruete ruffe rurec ruter rutte ruutu tefe terce teret tereu terre tert- teter tetr- tette treer treet trefe treff trere trete trett treut truce truer truff trute ttttt tucet tuctu tuffe tufte turet turre turtu turut tutee tutte tuuru u-cee ufere urter uruce urucu urutu uter- utter uttur uturu uuuuu