能力拓展，补全对话。 A: Good morning. 1._____are you from? B: I'm from America. A: Do you work in a middle school? B: 2._____, I do. I 3._____English. A: Can you 4._____Chinese? B: Yes, a little. I go to Chinese classes every week. A: 6._____ have you been in Beijing? B: For three years. A: Do you 7._____any children? B: Yes, I have a son and a daughter. A: Are they here8._____you? B: Yes, they are. 1._____ 2.______ 3._____ 4._____5._____ 6._____7._____8._____