nksl knsl nskl snkl ksnl sknl nkls knls nlks lnks klns lkns nslk snlk nlsk lnsk slnk lsnk ksln skln klsn lksn slkn lskn
Note: these 'words' (valid or invalid) are all the permutations of the word nksl. These words are obtained by scrambling the letters in nksl.