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One thing shocked me in the America is the culture difference between China and America.
　　One of my American friends, a professor in a university, has a boy at five when I was there. Such a little boy had a girlfriend at five too. The boy always invited her wherever his family went.The little boy introduced her to me when I met her the first time, "This is my girlfriend." I couldn't help laughing. He seriously answered my laugh: “Do you think I'll marry her? No way!”
　　How different the two cultures are at the point of having a girlfriend.