Co: Within the patent offices there are always budget limitations and staffing constraints that make it difficult to attack all goals at once.

CO：在专利机构中总是存在预算紧张和人员安排的问题，一下子实现所有的目标非常困难。

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Still, her profile makes her difficult to attack, and Rick Lazio's Senate candidacy has to help the GOP nominee.

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It's very difficult to attack a team that defends with nine players.

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The incoherence of this stance makes it conveniently difficult to attack.

ECONOMIST: Gay marriage