补全对话。

A: Good morning, madam!

B: Good morning, sir!

A: You look worried. (1)______?

B: My son got lost when I was talking with my friend in the park. I've looked for him everywhere,

    but I can't find him. What shall I do?

A: (2)______. Tell us something about him, and we can help you.

B: Thank you, sir.

A: Now please tell me (3)______.

B: He's six years old.

A: (4)______?

B: He's thin and tall with big eyes.

A: What is he wearing today?

B: He's wearing a white T-shirt and blue jeans.

A: (5)______?

B: It's 13803677057.

A: OK. We'll call you as soon as we find him.

B: Thank you very much.

抗血清的鉴定方法？