flank lfank falnk aflnk lafnk alfnk flnak lfnak fnlak nflak lnfak nlfak fanlk afnlk fnalk nfalk anflk naflk lanfk alnfk lnafk nlafk anlfk nalfk flakn lfakn falkn aflkn lafkn alfkn flkan lfkan fklan kflan lkfan klfan fakln afkln fkaln kfaln akfln kafln lakfn alkfn lkafn klafn aklfn kalfn flnka lfnka fnlka nflka lnfka nlfka flkna lfkna fklna kflna lkfna klfna fnkla nfkla fknla kfnla nkfla knfla lnkfa nlkfa lknfa klnfa nklfa knlfa fankl afnkl fnakl nfakl anfkl nafkl faknl afknl fkanl kfanl akfnl kafnl fnkal nfkal fknal kfnal nkfal knfal ankfl nakfl aknfl kanfl nkafl knafl lankf alnkf lnakf nlakf anlkf nalkf laknf alknf lkanf klanf aklnf kalnf lnkaf nlkaf lknaf klnaf nklaf knlaf anklf naklf aknlf kanlf nkalf knalf
Note: these 'words' (valid or invalid) are all the permutations of the word flank. These words are obtained by scrambling the letters in flank.