con-, 强调。-fid, 信任，词源同faith, fiance. 即与信任的人分享的私密信息。

1. National security is the stock excuse for keeping things confidential.

国家安全常被用作对一些事情保密的挡箭牌。

2. From time to time he passed on confidential information to him.

他时不时告诉他一些机密信息。

3. Police are investigating the disappearance from council offices of confidential files.

警察正在调查市政办公室机密档案被盗一案。

4. She accused them of leaking confidential information about her private life.

她指责他们泄露其私生活的秘密。

5. His face suddenly turned solemn, his voice confidential.

他脸上的神情突然严肃起来，声音也压低了。