bkil kbil bikl ibkl kibl ikbl bkli kbli blki lbki klbi lkbi bilk iblk blik lbik ilbk libk kilb iklb klib lkib ilkb likb
Note: these 'words' (valid or invalid) are all the permutations of the word bkil. These words are obtained by scrambling the letters in bkil.