nifes infes nfies fnies ifnes fines niefs inefs neifs enifs ienfs einfs nfeis fneis nefis enfis fenis efnis ifens fiens iefns eifns feins efins nifse infse nfise fnise ifnse finse nisfe insfe nsife snife isnfe sinfe nfsie fnsie nsfie snfie fsnie sfnie ifsne fisne isfne sifne fsine sfine niesf inesf neisf enisf iensf einsf nisef insef nsief snief isnef sinef nesif ensif nseif sneif esnif senif iesnf eisnf isenf sienf esinf seinf nfesi fnesi nefsi enfsi fensi efnsi nfsei fnsei nsfei snfei fsnei sfnei nesfi ensfi nsefi snefi esnfi senfi fesni efsni fseni sfeni esfni sefni ifesn fiesn iefsn eifsn feisn efisn ifsen fisen isfen sifen fsien sfien iesfn eisfn isefn siefn esifn seifn fesin efsin fsein sfein esfin sefin
Note: these 'words' (valid or invalid) are all the permutations of the word nifes. These words are obtained by scrambling the letters in nifes.