tuber utber tbuer btuer ubter buter tuebr utebr teubr etubr uetbr eutbr tbeur bteur tebur etbur betur ebtur ubetr buetr uebtr eubtr beutr ebutr tubre utbre tbure bture ubtre butre turbe utrbe trube rtube urtbe rutbe tbrue btrue trbue rtbue brtue rbtue ubrte burte urbte rubte brute rbute tuerb uterb teurb eturb uetrb eutrb tureb utreb trueb rtueb urteb ruteb terub etrub treub rteub ertub retub uertb eurtb uretb ruetb erutb reutb tberu bteru tebru etbru betru ebtru tbreu btreu trbeu rtbeu brteu rbteu terbu etrbu trebu rtebu ertbu retbu bertu ebrtu bretu rbetu erbtu rebtu ubert buert uebrt eubrt beurt eburt ubret buret urbet rubet bruet rbuet uerbt eurbt urebt ruebt erubt reubt berut ebrut breut rbeut erbut rebut
Note: these 'words' (valid or invalid) are all the permutations of the word tuber. These words are obtained by scrambling the letters in tuber.