-tree c-tec ccccc ccett ceere ceese cerc- cerce cercs cerec cerer ceres ceret cerre cerrs cerse cerss certe certs cesce cescr cesse ceste cests cetes cette crece creer crees cresc crese cress crete crres csere cstcc ctree cttee ecser eeeee erecs erect erere erest erets erres erses erste ersts erte erter ertes esces escrt esect esere esser esses essse estce estee ester estes estet estre etest etete etree etres etter ettes recce recet rect- recte rects reece reecs reere reese reest rere- reree reres reret resee reses reset resse reste restr rests retee reter retes rette retts s-tec scere scert screc scree scter sctrs secre secte sects seece seere seers seese seest seete serce serec serer seres seret serre serse serss sert- serte serts sesce seser seses sesse seste setec setee seter setse sette setts sssss steer stees steet sterc stere sterr sters stert stete stets stree stret strrs teers teese teest teets terce teres teret terre terrs terse tert- tesse teste tests teter tetes tetr- tette treer trees treet trere tres- trese tress trest trete trets trett trsce tsere tsets tsrcs ttest ttttt