29. B (interchange)
30. A (announcer)
31. A (that people use)
32. D (formal)
33. D (in)
34. D (that)
35. If you had a 15-year-old boy staying up too late and playing games endlessly, what would you do?
36. I am happy that you always revise tour lessons carefully before tests.
37. It is impossible for all local residents to stay during the social distancing.
38. Da Nang is the most attractive city in VN.
39. The man giving the charity considerable money is generous.
40. Lan's brother told her to follow his instructions.
