steil tseil setil estil tesil etsil stiel tsiel sitel istel tisel itsel seitl esitl sietl isetl eistl iestl teisl etisl tiesl itesl eitsl ietsl steli tseli setli estli tesli etsli stlei tslei sltei lstei tlsei ltsei selti eslti sleti lseti elsti lesti telsi etlsi tlesi ltesi eltsi letsi stile tsile sitle istle tisle itsle stlie tslie sltie lstie tlsie ltsie silte islte slite lsite ilste liste tilse itlse tlise ltise iltse litse seilt esilt sielt iselt eislt ieslt selit eslit sleit lseit elsit lesit silet islet sliet lsiet ilset liset eilst ielst elist leist ilest liest teils etils tiels itels eitls ietls telis etlis tleis lteis eltis letis tiles itles tlies lties iltes lites eilts ielts elits leits ilets liets
Note: these 'words' (valid or invalid) are all the permutations of the word steil. These words are obtained by scrambling the letters in steil.