undercover work

基本解释

The operation followed months of undercover police work that gathered evidence of an extraordinarily lucrative empire.
經過數月的秘密工作，收集了這個非常有利可圖的團夥的証據之後，警察展開了這次行動。
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.
另一方麪，理查德·沃爾什身上沒有傑尅·鮑爾那些亡命之徒的紋身——其中一些是做臥底時紋上去的，但大部分都是傑尅個人生活的記錄。
Undercover agents are police who work undercover to investigate crime and are totally different from little security informants.
警察從事秘密的調查活動才叫臥底，完全不同於治安小信息員。

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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