【正确答案】People are easy to be tricked by the temporary friendship, which seems to be sound, while in fact, superficial. Friendship and fraternization are not the same. Americans treat others with fraternization, but it doesn' t mean friendship, for the temporary contact doesn' t mean they want to keep in touch in the future. Only when people have the same interests, hobbies and the same values, can the forever friendship be possible. The high flexibility of the American society is one of the reasons why Americans cannot keep a permanent friendship.