twins wtins tiwns itwns witns iwtns twnis wtnis tnwis ntwis wntis nwtis tinws itnws tniws ntiws intws nitws wints iwnts wnits nwits inwts niwts twisn wtisn tiwsn itwsn witsn iwtsn twsin wtsin tswin stwin wstin swtin tiswn itswn tsiwn stiwn istwn sitwn wistn iwstn wsitn switn iswtn siwtn twnsi wtnsi tnwsi ntwsi wntsi nwtsi twsni wtsni tswni stwni wstni swtni tnswi ntswi tsnwi stnwi nstwi sntwi wnsti nwsti wsnti swnti nswti snwti tinsw itnsw tnisw ntisw intsw nitsw tisnw itsnw tsinw stinw istnw sitnw tnsiw ntsiw tsniw stniw nstiw sntiw instw nistw isntw sintw nsitw snitw winst iwnst wnist nwist inwst niwst wisnt iwsnt wsint swint iswnt siwnt wnsit nwsit wsnit swnit nswit snwit inswt niswt isnwt sinwt nsiwt sniwt
Note: these 'words' (valid or invalid) are all the permutations of the word twins. These words are obtained by scrambling the letters in twins.