Sure! Here are the completed sentences:

1. What do teenagers fond of?

2. Tourists are keen to see the terraced fields.

3. I do DIY in my freetime.

4. She’s crazy to upload pictures on Facebook.

5. How many ethnic groups are there in Vietnam?

6. Women play an important role in Thai family life.

7. She uploads her pictures on Facebook.

8. If you cook dinner, I will make a cake.

9. If it doesn't rain, they will go camping.

10. You stay healthy if you eat a banana every day.

11. You will pass the final exam if you study hard.

12. There won’t be any interesting activity during Tet here.

13. They watch Times Square’s New Year’s Eve Ball drop.

14. Vietnam people give lucky money to old people and children.

15. Linh loves to listen to pop music.