rough orugh ruogh urogh ourgh uorgh roguh orguh rgouh grouh ogruh goruh rugoh urgoh rguoh gruoh ugroh guroh ougrh uogrh ogurh gourh ugorh guorh rouhg oruhg ruohg urohg ourhg uorhg rohug orhug rhoug hroug ohrug horug ruhog urhog rhuog hruog uhrog hurog ouhrg uohrg ohurg hourg uhorg huorg roghu orghu rgohu grohu ogrhu gorhu rohgu orhgu rhogu hrogu ohrgu horgu rghou grhou rhgou hrgou ghrou hgrou oghru gohru ohgru hogru ghoru hgoru rugho urgho rguho gruho ugrho gurho ruhgo urhgo rhugo hrugo uhrgo hurgo rghuo grhuo rhguo hrguo ghruo hgruo ughro guhro uhgro hugro ghuro hguro oughr uoghr oguhr gouhr ugohr guohr ouhgr uohgr ohugr hougr uhogr huogr oghur gohur ohgur hogur ghour hgour ughor guhor uhgor hugor ghuor hguor
Note: these 'words' (valid or invalid) are all the permutations of the word rough. These words are obtained by scrambling the letters in rough.