Here's how you can fill out the exercise based on the prompts given:

1. A: What do people do to celebrate Christmas?
B: They **put up** a Christmas tree.

2. A: What do people do to celebrate Halloween?
B: They wear **costumes**.

3. A: What do people do to celebrate Lunar New Year?
B: They watch **lion dance**.

4. A: What do people do to celebrate New Year's Eve?
B: They watch **fireworks**.

5. A: What do people do to celebrate Lunar New Year?
B: They give **money**.

6. A: What do people do to celebrate Children's Day?
B: They have **fun activities**.

Feel free to fill in any specific answers that align better with your lessons!