Answer:
1. The boy is too careless.- careless
2. The winds are very strong.- strong
3. The baby slept soundly.- soundly
4. The soldiers fought the war valiantly.- valiantly
5. Joey always tries his best.- best
6. Surely you are mistaken.- surely
7. The movie is to end soon.- soon
8. Your friend messaged again.- again
9. I did my homework already.- already
10. I was rather busy.- rather
11. Is your mother within?- within
12. We looked for the lost puppy everywhere.- everywhere
13. We do not know her.- not
14. How long is the trip?- long
15. Monica seldom visits here.- seldom, here