quid uqid qiud iqud uiqd iuqd qudi uqdi qdui dqui udqi duqi qidu iqdu qdiu dqiu idqu diqu uidq iudq udiq duiq iduq diuq
Note: these 'words' (valid or invalid) are all the permutations of the word quid. These words are obtained by scrambling the letters in quid.