So, today, what do you think are the greatest national security threats or threats to America's interests.

现在，您认为,什么会严重威胁美国国家安全,威胁美国国家利益。

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Especially in the United States, it's a law that you have to wear your seatbelt.

尤其在美国，法律规定开车时必须系好安全带。

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