an undercover agent
密探
an undercover operation/investigation
秘密行动╱调查
1.秘密的,暗中进行的,隐蔽的,掩蔽下的
1.working or done secretly in order to catch criminals, get secret information, etc.
1.When an undercover British spy is killed in his flat, Hannay finds himself accused of murder and caught up in a deadly conspiracy.
一个受到保护的英国间谍死在他的公寓中，哈内发现自己被阴谋卷入改案。
2.No undercover or anything, just a message saying that they were the police.
警方并没有秘密行事，只是发了条消息告诉瑞姆他们是警方。
3."A reporter surnamed Zhou said that I need evidence. So I decided to go undercover to collect it, " he said.
他表示：“一位姓周的记者说我需要证据。所以，我就决定当卧底来收集证据了。”
4.Bobby inadvertently put out an undercover months of the Women's International Criminal Police, and a section of her situation.
波比无意中救一了个卧底的国际女刑警，和她有了一段情。
5.The man had been arrested while trying to sell marijuana to undercover officers, one of the officials familiar with the investigation said.
一名熟知调查的官员说，这名男子是在试图向卧底警察贩卖大麻时被捕的。
6.Once I was ready to start dating I found myself in an undercover relationship with someone too ashamed to be seen in public with me.
曾有一次我觉得自己已经准备开始约会了，但发现对方觉得在公众被人看到与我一起很丢人只想跟我保持地下关系。
7.Idaho Republican Sen. Larry Craig's explanation of why his foot touched that of an undercover policeman in a men's room.
涉嫌勾搭男同性恋者的爱达荷州共和党参议员拉里。克雷格，对他在公共卫生间为什么脚会碰到一名便衣警察脚的解释。
8.I mean I put two years of work - nine months of it undercover - to gather enough evidence to indict Dante Arete. The case was almost made.
我的意思是我用了两年时间收集足以起诉丹蒂·阿雷特的证据，其中9个月是做卧底。
9.The men had been recovering at a San Antonio, Texas hospital since being rescued in an undercover operation last week.
这几人上周被秘密救出后，被送往德克萨斯州圣安东尼奥的一家医院，目前正在恢复中。
10.Did not last long, Mark was the undercover identity of the final 5-year girlfriend exposed contacts.
好景不长，马克的卧底身份最终遭交往5年的女友揭发。