ebook beook eobok oebok boeok obeok ebook beook eobok oebok boeok obeok eoobk oeobk eoobk oeobk ooebk ooebk booek oboek booek oboek oobek oobek eboko beoko eobko oebko boeko obeko ebkoo bekoo ekboo keboo bkeoo kbeoo eokbo oekbo ekobo keobo okebo koebo bokeo obkeo bkoeo kboeo okbeo kobeo eboko beoko eobko oebko boeko obeko ebkoo bekoo ekboo keboo bkeoo kbeoo eokbo oekbo ekobo keobo okebo koebo bokeo obkeo bkoeo kboeo okbeo kobeo eookb oeokb eookb oeokb ooekb ooekb eokob oekob ekoob keoob okeob koeob eokob oekob ekoob keoob okeob koeob ookeb ookeb okoeb kooeb okoeb kooeb booke oboke booke oboke oobke oobke bokoe obkoe bkooe kbooe okboe koboe bokoe obkoe bkooe kbooe okboe koboe ookbe ookbe okobe koobe okobe koobe
Note: these 'words' (valid or invalid) are all the permutations of the word ebook. These words are obtained by scrambling the letters in ebook.