treen rteen teren etren reten erten treen rteen teren etren reten erten teern etern teern etern eetrn eetrn reetn eretn reetn eretn eertn eertn trene rtene terne etrne retne ertne trnee rtnee tnree ntree rntee nrtee tenre etnre tnere ntere entre netre rente ernte rnete nrete enrte nerte trene rtene terne etrne retne ertne trnee rtnee tnree ntree rntee nrtee tenre etnre tnere ntere entre netre rente ernte rnete nrete enrte nerte teenr etenr teenr etenr eetnr eetnr tener etner tneer nteer enter neter tener etner tneer nteer enter neter eentr eentr enetr neetr enetr neetr reent erent reent erent eernt eernt renet ernet rneet nreet enret neret renet ernet rneet nreet enret neret eenrt eenrt enert neert enert neert
Note: these 'words' (valid or invalid) are all the permutations of the word treen. These words are obtained by scrambling the letters in treen.