涉及国防采购的文件属于机密资料,未经授权不得复制。Shèjí guófáng cǎigòu de wénjiàn shǔyú jīmì zīliào, wèi jīng shòuquán bù dé fùzhì.Documents involving defence procurement are classified materials and may not be copied without authorisation.
这份机密文件只有经理才能打开。Zhè fèn jīmì wénjiàn zhǐyǒu jīnglǐ cái néng dǎkāi.Only the manager can open this confidential document.
公司的技术机密绝对不能告诉外人。Gōngsī de jìshù jīmì juéduì bù néng gàosu wàirén.The company's technical secrets must never be told to outsiders.