sowff oswff swoff wsoff owsff wosff sofwf osfwf sfowf fsowf ofswf foswf swfof wsfof sfwof fswof wfsof fwsof owfsf wofsf ofwsf fowsf wfosf fwosf sowff oswff swoff wsoff owsff wosff sofwf osfwf sfowf fsowf ofswf foswf swfof wsfof sfwof fswof wfsof fwsof owfsf wofsf ofwsf fowsf wfosf fwosf soffw osffw sfofw fsofw ofsfw fosfw soffw osffw sfofw fsofw ofsfw fosfw sffow fsfow sffow fsfow ffsow ffsow offsw fofsw offsw fofsw ffosw ffosw swffo wsffo sfwfo fswfo wfsfo fwsfo swffo wsffo sfwfo fswfo wfsfo fwsfo sffwo fsfwo sffwo fsfwo ffswo ffswo wffso fwfso wffso fwfso ffwso ffwso owffs woffs ofwfs fowfs wfofs fwofs owffs woffs ofwfs fowfs wfofs fwofs offws fofws offws fofws ffows ffows wffos fwfos wffos fwfos ffwos ffwos
Note: these 'words' (valid or invalid) are all the permutations of the word sowff. These words are obtained by scrambling the letters in sowff.