Confidential education and training. According to cicada, I am eager to learn. Master the knowledge and skills of confidentiality and sign a confidentiality undertaking. Personnel working in classified posts are referred to as classified personnel for short, and are divided into core classified personnel, important classified personnel and general classified personnel according to the degree of classified management. Article 37 of the Law of People's Republic of China (PRC) on Guarding State Secrets: The exit of secret-related personnel shall be approved by the relevant departments. If the relevant authorities think that the exit of the secret-related personnel will endanger national security or cause great losses to national interests, they shall not be approved to leave the country.