unbed nubed ubned buned nbued bnued unebd nuebd uenbd eunbd neubd enubd ubend buend uebnd eubnd beund ebund nbeud bneud nebud enbud benud ebnud unbde nubde ubnde bunde nbude bnude undbe nudbe udnbe dunbe ndube dnube ubdne budne udbne dubne bdune dbune nbdue bndue ndbue dnbue bdnue dbnue unedb nuedb uendb eundb neudb enudb undeb nudeb udneb duneb ndueb dnueb uednb eudnb udenb duenb edunb deunb nedub endub ndeub dneub ednub denub ubedn buedn uebdn eubdn beudn ebudn ubden buden udben duben bduen dbuen uedbn eudbn udebn duebn edubn deubn bedun ebdun bdeun dbeun edbun debun nbedu bnedu nebdu enbdu bendu ebndu nbdeu bndeu ndbeu dnbeu bdneu dbneu nedbu endbu ndebu dnebu ednbu denbu bednu ebdnu bdenu dbenu edbnu debnu
Note: these 'words' (valid or invalid) are all the permutations of the word unbed. These words are obtained by scrambling the letters in unbed.