But there were legal objections to a covert operation.

但是法律不允许这样的秘密行动。

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Designed for commando and espionage operation, the main strength of a covert ops vessel is the ability to travel unseen through enemy territory and avoid unfavorable encounters.

主要用于侦察行动，其主要长项是能够隐身穿越敌战区，避免不必要的遭遇战。

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But approaching photography like a covert operation is not the most ethical way to get a great shot.

BBC: Taking photographs of people

But HP drew headlines for news of the covert operation led by the HP board's chairman, Patricia Dunn.

FORBES: Companies, People, Ideas

In a covert operation like this, you don't expect much more information.

CNN: Saddam Hussein