undercover work

基本解释

The operation followed months of undercover police work that gathered evidence of an extraordinarily lucrative empire.
经过数月的秘密工作，收集了这个非常有利可图的团伙的证据之后，警察展开了这次行动。
On the other hand, Richard Walsh lacked Jack Bauer's outlaw tattoos - a few gained in undercover work; most part of Jack's personal roadmap.
另一方面，理查德·沃尔什身上没有杰克·鲍尔那些亡命之徒的纹身——其中一些是做卧底时纹上去的，但大部分都是杰克个人生活的记录。
Undercover agents are police who work undercover to investigate crime and are totally different from little security informants.
警察从事秘密的调查活动才叫卧底，完全不同于治安小信息员。

Such was the professionalism of Chris Gaubatz's undercover work that he was given boxes of documents to dispose of - which he did, in a fashion.
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Evidence showed that his involvement was not undercover work.
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Mr Fitzgerald responded in a press conference on Friday that people who work undercover for their country need to know that they will not be unmasked lightly, and that when their cover is blown it is crucial that officials co-operate with any investigation.
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