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A

   Look at the photo. Can you see the boy in the photo? That is an American (美国的) boy. He is my good friend. His name is Jim Green. He is tall, and his hair is blond. He likes blue. Oh, who is that girl? That is his sister Betty Green. She has a long face and big eyes. She likes blue, too. They are in Beijing now. They are in No. 4 Middle School. Jim is in Class 6, Grade 8. His Chinese teacher is Miss Wang. Betty is in Class 2, Grade 7. Her Chinese teacher is Mr. Zhong. Jim is twelve. How old is Betty? Sorry, I don't know. Can you guess?