official secrets

• n. 涉及国家安全方面的秘密

official secrets的用法和样例：

例句

1. Civil servant is required to sign the official secrets act.
   公务员须签署遵守公务保密条例。
2. Civil Servants are required to sign the Official Secrets Act.
   公务员须签署遵守公务保密条例。
3. Government employees swear an oath not to reveal official secrets.
   政府雇员宣誓不泄露官方机密。
4. The government has invoked the Official Secrets Act in having the book banned.
   政府援引国家机密保密法以禁该书。