根据上下文补全对话。

A: Hi, Linda! Where is Jack?

B: He is in the laboratory. up?

A: I found a blue schoolbag. I think it's his.

B: I don't so. His is green.

A: Then is it?

B: It might be Alan's. He was in the laboratory this morning.

A: But Alan's schoolbag is much smaller.

B: Well, let's have a what's in it.

A: Oh, it must be Nancy's. Look! Her school ID card is in it.

B: You're . Let's go and give it to her.

A: Sure. She is in the reading room now.