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The killing involved 27 undercover agents travelling on forged passports .

此次暗杀中，27个秘密特工使用伪造的护照出行。

Airport screeners still fail undercover tests of their ability to spot concealed weapons .

机场扫描系统的秘密测试结果表明，它还不能查出隐秘武器装备。

Undercover informants can be more useful to the groups they monitor than to their paymasters .

相比给他们发付薪水的部门，秘密线人们对他们所监视的团伙的作用可能更大。

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。

Key messages to staff should never go undercover , even if one boss had to don a disguise to find this out .

向员工传递的重要信息绝对不能成为秘密，即使得有位老板披上伪装去发现这一点。