Here are the correct answers for the blanks in the passage:

1. **C. in**
2. **B. walks**
3. **A. making**
4. **A. enjoys**
5. **D. goes out**
6. **B. have fun**
7. **A. time**
8. **B. at**

Thus, the completed sentences would read:

"What do you like doing best **in** your spare time? My cousin Paul likes going (2) **for walks** in the country and **making** photos. Sometimes he (4) **enjoys** with his friends, and they (5) **go out** at the park or at the beach. They always (6) **have fun**. His brother Chris isn't (7) **at** home. He spends most of the (8) **time**."