drank rdank darnk adrnk radnk ardnk drnak rdnak dnrak ndrak rndak nrdak danrk adnrk dnark ndark andrk nadrk randk arndk rnadk nradk anrdk nardk drakn rdakn darkn adrkn radkn ardkn drkan rdkan dkran kdran rkdan krdan dakrn adkrn dkarn kdarn akdrn kadrn rakdn arkdn rkadn kradn akrdn kardn drnka rdnka dnrka ndrka rndka nrdka drkna rdkna dkrna kdrna rkdna krdna dnkra ndkra dknra kdnra nkdra kndra rnkda nrkda rknda krnda nkrda knrda dankr adnkr dnakr ndakr andkr nadkr daknr adknr dkanr kdanr akdnr kadnr dnkar ndkar dknar kdnar nkdar kndar ankdr nakdr akndr kandr nkadr knadr rankd arnkd rnakd nrakd anrkd narkd raknd arknd rkand krand akrnd karnd rnkad nrkad rknad krnad nkrad knrad ankrd nakrd aknrd kanrd nkard knard
Note: these 'words' (valid or invalid) are all the permutations of the word drank. These words are obtained by scrambling the letters in drank.