Prefix exercise

http://admin.sfcc.edu/~jgraney/vocabulary/prefix_page.html
http://205.126.22.50/language/lessons/prefixes.html

1. Miyoko her shoes. (placed incorrectly)

2. My mother an old rocking chair. (finished again)

3. Jamie his jeans. (washed before)

4. The artist the orange paint. (applied again)

5. Father the furniture. (arranged again)

6. The guard the door. (opposite of locked)

7. The doctor the patient. (admitted again)

8. The pupil . (behaved incorrectly)

9. The workers must the bridge. (build again)

10. The person the check. (dated before)

I just get 5/10. Here is my right answer:
4 reapplied
5 rearranged
7 readmitted
8 misbehaved
10 predated

Unfortunately, i can't check with the wrong answers. Here they are:
1 misplaced
2 refinished
3 prewashed
6 unlocked
9 rebuild

I still don't know why they are wrong. Anyone help me?