urked ruked ukred kured rkued krued urekd ruekd uerkd eurkd reukd erukd ukerd kuerd uekrd eukrd keurd ekurd rkeud kreud rekud erkud kerud ekrud urkde rukde ukrde kurde rkude krude urdke rudke udrke durke rduke druke ukdre kudre udkre dukre kdure dkure rkdue krdue rdkue drkue kdrue dkrue uredk ruedk uerdk eurdk reudk erudk urdek rudek udrek durek rduek druek uedrk eudrk uderk duerk edurk deurk reduk erduk rdeuk dreuk edruk deruk ukedr kuedr uekdr eukdr keudr ekudr ukder kuder udker duker kduer dkuer uedkr eudkr udekr duekr edukr deukr kedur ekdur kdeur dkeur edkur dekur rkedu kredu rekdu erkdu kerdu ekrdu rkdeu krdeu rdkeu drkeu kdreu dkreu redku erdku rdeku dreku edrku derku kedru ekdru kderu dkeru edkru dekru
Note: these 'words' (valid or invalid) are all the permutations of the word urked. These words are obtained by scrambling the letters in urked.