carkw acrkw crakw rcakw arckw rackw cakrw ackrw ckarw kcarw akcrw kacrw crkaw rckaw ckraw kcraw rkcaw krcaw arkcw rakcw akrcw karcw rkacw kracw carwk acrwk crawk rcawk arcwk racwk cawrk acwrk cwark wcark awcrk wacrk crwak rcwak cwrak wcrak rwcak wrcak arwck rawck awrck warck rwack wrack cakwr ackwr ckawr kcawr akcwr kacwr cawkr acwkr cwakr wcakr awckr wackr ckwar kcwar cwkar wckar kwcar wkcar akwcr kawcr awkcr wakcr kwacr wkacr crkwa rckwa ckrwa kcrwa rkcwa krcwa crwka rcwka cwrka wcrka rwcka wrcka ckwra kcwra cwkra wckra kwcra wkcra rkwca krwca rwkca wrkca kwrca wkrca arkwc rakwc akrwc karwc rkawc krawc arwkc rawkc awrkc warkc rwakc wrakc akwrc kawrc awkrc wakrc kwarc wkarc rkwac krwac rwkac wrkac kwrac wkrac
Note: these 'words' (valid or invalid) are all the permutations of the word carkw. These words are obtained by scrambling the letters in carkw.