Here are the answers to the questions based on the provided text:

4. Be careful not to drop it; it's very ______.
- b. fragile

5. I hope he'll teach me ______ to do eggshell carving.
- c. how

6. Nowadays people ______ hours sitting in front of computers.
- a. spend

7. I join in a photography club, and all members love ______ a lot of beautiful photos.
- b. taking

8. What does your father do ______ his free time?
- a. in

9. My sister is very keen on swimming, and she goes swimming three ______ a week.
- d. times

10. She finds ______ flowers interesting because it helps her relax.
- d. arranging