LUYỆN TẬP - CẤU TẠO TỪ VÀ TỪ LOẠI

Here's a guide to the answers for the vocabulary exercise you provided, focusing on word formation and parts of speech:

1. A - inform
2. B - information
3. C - informal
4. D - informative
5. A - interest
6. B - interesting
7. C - interested
8. D - interestingly
9. A - native
10. B - nation
11. C - national
12. D - nationality
13. A - cheap
14. B - inexpensive
15. C - expensively
16. D - expensive
17. A - interact
18. B - interaction
19. C - interactive
20. D - interactively
21. A - develop
22. B - developed
23. C - developing
24. D - development
25. A - increase
26. B - increased
27. C - increasingly
28. D - incredible
29. A - invention
30. B - invent
31. C - inventing
32. D - inventions
33. A - limit
34. B - limited
35. C - limitation
36. D - limitations
37. A - communicate
38. B - communicative
39. C - communication
40. D - communications
41. A - communicate
42. B - communicative
43. C - communication
44. D - communications
45. A - usage
46. B - using
47. C - use
48. D - used
49. A - develop
50. B - developed

For the exercise 23 answers:
1. C - at
2. B - on
3. D - for
4. A - in
5. C - with
6. D - to
7. B - in

If you need further clarifications or explanations about any specific words or formats, feel free to ask!