ulyfl luyfl uylfl yulfl lyufl ylufl ulfyl lufyl uflyl fulyl lfuyl fluyl uyfll yufll ufyll fuyll yfull fyull lyful ylful lfyul flyul yflul fylul ulylf luylf uyllf yullf lyulf ylulf ullyf lulyf ullyf lulyf lluyf lluyf uyllf yullf ulylf luylf ylulf lyulf lyluf ylluf llyuf llyuf ylluf lyluf ulfly lufly uflly fully lfuly fluly ullfy lulfy ullfy lulfy llufy llufy uflly fully ulfly lufly fluly lfuly lfluy flluy llfuy llfuy flluy lfluy uyfll yufll ufyll fuyll yfull fyull uylfl yulfl ulyfl luyfl ylufl lyufl uflyl fulyl ulfyl lufyl fluyl lfuyl yflul fylul ylful lyful flyul lfyul lyflu ylflu lfylu flylu yfllu fyllu lylfu yllfu llyfu llyfu yllfu lylfu lflyu fllyu llfyu llfyu fllyu lflyu yfllu fyllu ylflu lyflu flylu lfylu
Note: these 'words' (valid or invalid) are all the permutations of the word ulyfl. These words are obtained by scrambling the letters in ulyfl.