16. Bell (success) __successfully_ demonstrated his invention.   

17. (fortunate) Unfortunately___, I lost my keys on the way home.   

18. Each of my friends has (difference) __different_ characters. 

19. The boys shouted (excite) _excitedly__. 

20. You must put all medicines in (lock) _locked__ cupboards. 

21. Those clothes are (suit) _suitable__ for cold weather. 

22. Most teenagers like taking part in (communal) _community__ service. 

23. Bell and Watson successfully___ demonstrated the invention at countless exhibitions.
24. Last week, Suga actively (participation) __participated_ in social work.

25. I'm not (satisfaction) _satisfied__ with the way he cut my hair. 

26. He always talks about his son (pride) _proudly__. 

27. Nam likes acting and outdoor (act) __activities_. 

28. Is that ladder (safety) _safe__? 

29. We need to (electric) __electrify_ the whole country as soon as possible.
30. Hard work always brings (succeed) __success_.