rebec erbec rbeec breec ebrec berec reebc erebc reebc erebc eerbc eerbc rbeec breec rebec erbec berec ebrec eberc beerc eebrc eebrc beerc eberc rebce erbce rbece brece ebrce berce recbe ercbe rcebe crebe ecrbe cerbe rbcee brcee rcbee crbee bcree cbree ebcre becre ecbre cebre bcere cbere reecb erecb reecb erecb eercb eercb receb erceb rceeb creeb ecreb cereb receb erceb rceeb creeb ecreb cereb eecrb eecrb ecerb ceerb ecerb ceerb rbece brece rebce erbce berce ebrce rbcee brcee rcbee crbee bcree cbree recbe ercbe rcebe crebe ecrbe cerbe becre ebcre bcere cbere ecbre cebre ebecr beecr eebcr eebcr beecr ebecr ebcer becer ecber ceber bceer cbeer eecbr eecbr ecebr ceebr ecebr ceebr becer ebcer bceer cbeer ecber ceber
Note: these 'words' (valid or invalid) are all the permutations of the word rebec. These words are obtained by scrambling the letters in rebec.