1. They enjoying their vacation. (be)

2. The book based on the reviews. (interesting)

3. It we're running out of time. (like)

4. The students about the upcoming field trip. (excited)

5. She a natural talent for painting. (have)

6. The situation improving slowly. (be)

7. they have found a solution to the problem. (that)

8. The food at this restaurant . (delicious)

9. She have a lot of knowledge about the subject. (have)

10. It they have a strong connection with each other. (like)

11. It he knows the secret, but he won't tell anyone. (if)

12. It they have been waiting for hours. (though)

13. It the train is running late again. (if)

14. It the cat is stuck on the tree. (though)

15. It they have already made up their minds. (though)