You can't. Of course, the official seal of a middle school cannot be stamped casually. Not only middle schools, but also the official seals of any unit are kept by special personnel, and can't be stamped casually, because many legal issues are involved here. Therefore, preschool education cannot be stamped with the seal of middle school. Paragraph 2 of Article 5 of the Provisions of the Supreme People's Court on Several Issues Concerning the Trial of Economic Disputes Cases Suspected of Economic Crimes stipulates: "If the perpetrator signs an economic contract by engraving the official seal of the unit privately or using the official seal of the unit, a business letter of introduction or a blank contract stamped with the official seal, and the unit has obvious fault, and there is a causal relationship between the fault behavior and the economic loss of the victim, the unit shall be liable for compensation for the economic loss caused by the crime. In this case, the unit can claim compensation from the criminal who privately carved the official seal.