对美国人而言，美国是世界上最强的超级大国，而且美国人民是一群单纯的朋友。

And for the Americans, the United States is the world's number one superpower, and the American people are a very simple people.

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设计：整群抽样与单纯随机抽样。

DESIGN: a cluster sampling and simple randomized sampling survey.

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我喜欢这群青年们单纯的信心和希望在这世界保持美好标准的渴望。

I like seeing the pure faith of these youth, and their hope and desire to keep the good standard in this world.

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