阅读下面的对话完成任务。

A: Excuse me, Susan. （1）Is this your backpack?

B: No, it isn't. It's Jack's. （2）My backpack is green.

A: Is your computer game in the lost and found case?

B: No, it's Jack's. And that white eraser is Jack's, too.

A: Do you know Jack?

B: Yes, I do. （3）他是一个英国男孩。He's in Class One, Grade Seven.

A: Oh, what's his telephone number?

B: 100-2116

A: Is Miss Miller his English teacher?

B: Yes, you're right.