fiky ifky fkiy kfiy ikfy kify fiyk ifyk fyik yfik iyfk yifk fkyi kfyi fyki yfki kyfi ykfi ikyf kiyf iykf yikf kyif ykif
Note: these 'words' (valid or invalid) are all the permutations of the word fiky. These words are obtained by scrambling the letters in fiky.