-tree bbbee bcell be-er bebel beber becel becue becut beebe beele beete beeut belce belec belee belet bellb belle belue belur belut berbe bercu berec berel beret berle berre berru berte betee betel beter betle betre bett- bette betul beuer beule beure beute bleer bleet blere blete bleue bluer bluet blurb blure blurr blurt brebu brece breel breer breet brell brere brett breu- brrrr bruce bruer bruet brule brull brute btc-e btr-t bubbe buber buble bucet bucur buell bulb- bull- bulle bulul bulut burcu burel buret burle burru burte burtt buruc burut butec buter butle butte butut c-tec cblue ccccc ccell ccett ccrcl ccrel cctrl cebec ceber ceele ceere celeb celer cell- celle celte cerbu cerc- cerce cerec cerer ceret cerre certe cette cleer cleet clerc clere clete clett clubb clue- cluer clurr clute clutt crebe crece creel creer crele crell crete cretu creu- creue creul crrel cruce cruel cruet crule crull crure ctree ctrlc cttee ctulu cubbe cubeb cubel cuber cubub culbe culet culle cullu culur curce curel curer curet curle curll curlu curre cutcu cutee cuter cutle cuuel ebber ebbet ebble ebell eberl ebert eblul ebull ebure eccle eeeee eeler elect eleet elele eleut ellel eller ellet ellul elrec elulu eluru elute erbbe erber erect erere errtu erte ertel erter eruct etete etree ettel etter ettle eturu eucre euell euler eurel eurre lebce lebec lebel leber lebet lecce leece leell leere leert leleu lelle lerer letbe letre lette letur leuc- leuce lubbe luber luble lubur lucee lucet lucre lucur lulec lulle lulte luluc lulul lurer lurue lute- luter lutte rebbe rebec rebel reber rebet rebut recce recet rect- recte recue recur recut reece reere relee relet relte relue rere- reree reret retee retel reter rette reuel reuer reuet reule reute rubee rubel ruber ruble rucer rucul ruele ruell ruere ruete ruler rurec ruter rutle rutte rutul ruule ruutu tbtbt tbutt tcell teber tebet tectb tecul teele teell telce tele- telec teler teleu tell- telle terce teret tereu terre tert- tetel teter tetle tetr- tette tlell tlett tllbr treer treet trele trere trete trett treut trubu truce truel truer trule trull trute ttttt tuber tubul tucet tuctu tuell tuelt tulce tulet tulle turbe turbt turel turet turle turre turtu turul turut tutee tutel tutle tutte tuuru u-cee ubble uber- uccel uccle ucell uclue ulcer ullet ullur ultre ululu uluru urcel urelu urtel urter urtlu urubu uruce urucu urutu uter- utter uttur utube uturu uuuuu