读对话并回答问题。

Linda : Hello. I'm Linda.

Tony : Hi. I'm Tony. What's your last name, Linda?

Linda : It's Smith. What's your last name, Tony?

Tony : It's Brown.

1. What's her first name?

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2. What's his first name?

    _____________________

3. What's his last name?

    _____________________

4. What's her last name?

    _____________________

生物膜。