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Many people don't have the same hobbies, but they can still be good friends. Li Yang and Wang Li are good friends. Li Yang likes collecting stamps and often shows them to Wang Li. Wang Li doesn't like collecting things. He likes swimming. Wang Li often asks Li Yang to go swimming with him. But Li Yang always says he is busy. Yes, he is always busy with his stamps. "You should collect something," Li Yang often says to Wang Li. Wang Li likes playing the violin, but Li Yang doesn't. Li Yang likes playing the piano. They like to help each other. That's why they are good friends.