bebir ebbir bbeir bbeir ebbir bebir beibr ebibr biebr ibebr eibbr iebbr bbier bbier biber ibber biber ibber ebibr beibr eibbr iebbr biebr ibebr bebri ebbri bberi bberi ebbri bebri berbi ebrbi brebi rbebi erbbi rebbi bbrei bbrei brbei rbbei brbei rbbei ebrbi berbi erbbi rebbi brebi rbebi beirb ebirb bierb iberb eibrb iebrb berib ebrib breib rbeib erbib rebib bireb ibreb brieb rbieb irbeb ribeb eirbb ierbb eribb reibb irebb riebb bbire bbire bibre ibbre bibre ibbre bbrie bbrie brbie rbbie brbie rbbie birbe ibrbe bribe rbibe irbbe ribbe birbe ibrbe bribe rbibe irbbe ribbe ebirb beirb eibrb iebrb bierb iberb ebrib berib erbib rebib breib rbeib eirbb ierbb eribb reibb irebb riebb bireb ibreb brieb rbieb irbeb ribeb
Note: these 'words' (valid or invalid) are all the permutations of the word bebir. These words are obtained by scrambling the letters in bebir.