题目内容：

补全对话

A:1., Nina?

B: I don’t know. 2., Mary?

A: We’re going to the beach.

B: 3.?

A: We’re riding to the subway station. We take the train, then walk to the beach.

B: That sounds interesting.

A: Why don’t you come with us?

B: That’s a good idea. That must be much more fun than staying at home.

4.?

A: It’s not very far, only fifty kilometers.

B: 5.?

A: Next Friday morning. We’re coming back next Sunday afternoon.

B: OK! See you then.