serer esrer sreer rseer erser reser seerr eserr seerr eserr eesrr eesrr sreer rseer serer esrer reser erser eresr reesr eersr eersr reesr eresr serre esrre srere rsere ersre resre serre esrre srere rsere ersre resre srree rsree srree rsree rrsee rrsee errse rerse errse rerse rrese rrese seerr eserr seerr eserr eesrr eesrr serer esrer sreer rseer erser reser serer esrer sreer rseer erser reser eersr eersr eresr reesr eresr reesr srere rsere serre esrre resre ersre srree rsree srree rsree rrsee rrsee serre esrre srere rsere ersre resre rerse errse rrese rrese errse rerse erers reers eerrs eerrs reers erers erres reres erres reres rrees rrees eerrs eerrs erers reers erers reers reres erres rrees rrees erres reres
Note: these 'words' (valid or invalid) are all the permutations of the word serer. These words are obtained by scrambling the letters in serer.