1. 情景对话

A. There are forty letters. B. Thank you. C. I'm writing goodbye letters to all my friends at school. D. First I write the name of a friend.

1. （1） —What are you doing?

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3. （2） —What do you write in your letters?

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5. （3） —How many letters are there?

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7. （4） —Good luck for the future!

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