strou tsrou srtou rstou trsou rtsou storu tsoru sotru ostru tosru otsru srotu rsotu sortu osrtu rostu orstu trosu rtosu torsu otrsu rotsu ortsu struo tsruo srtuo rstuo trsuo rtsuo sturo tsuro sutro ustro tusro utsro sruto rsuto surto usrto rusto ursto truso rtuso turso utrso rutso urtso stour tsour sotur ostur tosur otsur stuor tsuor sutor ustor tusor utsor soutr osutr suotr usotr oustr uostr tousr otusr tuosr utosr outsr uotsr srout rsout sorut osrut rosut orsut sruot rsuot surot usrot rusot ursot sourt osurt suort usort ousrt uosrt roust orust ruost urost ourst uorst trous rtous torus otrus rotus ortus truos rtuos turos utros rutos urtos tours oturs tuors utors outrs uotrs routs oruts ruots urots ourts uorts
Note: these 'words' (valid or invalid) are all the permutations of the word strou. These words are obtained by scrambling the letters in strou.