gukh ugkh gkuh kguh ukgh kugh guhk ughk ghuk hguk uhgk hugk gkhu kghu ghku hgku khgu hkgu ukhg kuhg uhkg hukg khug hkug
Note: these 'words' (valid or invalid) are all the permutations of the word gukh. These words are obtained by scrambling the letters in gukh.