frows rfows forws ofrws rofws orfws frwos rfwos fwros wfros rwfos wrfos fowrs ofwrs fwors wfors owfrs wofrs rowfs orwfs rwofs wrofs owrfs worfs frosw rfosw forsw ofrsw rofsw orfsw frsow rfsow fsrow sfrow rsfow srfow fosrw ofsrw fsorw sforw osfrw sofrw rosfw orsfw rsofw srofw osrfw sorfw frwso rfwso fwrso wfrso rwfso wrfso frswo rfswo fsrwo sfrwo rsfwo srfwo fwsro wfsro fswro sfwro wsfro swfro rwsfo wrsfo rswfo srwfo wsrfo swrfo fowsr ofwsr fwosr wfosr owfsr wofsr foswr ofswr fsowr sfowr osfwr sofwr fwsor wfsor fswor sfwor wsfor swfor owsfr wosfr oswfr sowfr wsofr swofr rowsf orwsf rwosf wrosf owrsf worsf roswf orswf rsowf srowf osrwf sorwf rwsof wrsof rswof srwof wsrof swrof owsrf wosrf oswrf sowrf wsorf sworf
Note: these 'words' (valid or invalid) are all the permutations of the word frows. These words are obtained by scrambling the letters in frows.