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.
