30. B

31. C

32. A

33. D

34. B

35. C

36. B

37. B

38. D

39. B

40. A

19. C

20. B

21. A

22. D

23. B

24. A

9. B

10. D

11. A

12. A

13. C

14. B

15. B

16. D

17. A

18. B

IX. Complete the sentences with the correct form of the words in brackets.
1. Some people think that health is more important than money. (important)
2. The pollution in our city is much worse than it used to be. (bad)
3. My new teacher explained the lessons more clear than my old teacher. (clear)
4. He doesn’t play volleyball as well as his brother. (good)
5. Get rid of the sorrow! You will do it better next time. (good)
6. Communication is a lot easier than it was 50 years ago. (easy)
7. People in rural areas wear more simply than those in cities. (simple)
8. Robert arrived at the meeting later than Francis. (late)
9. These trousers are too wide. Do you have any that are narrower ? (narrow)
10. My mother always gets up earlier than everybody else in the house. (early)
11. Rene speaks more fluently than the other ESL students in the class. (fluent)
12. Can’t you think of anything more intelligent to say? (intelligent)
13. I think his new book is much more boring than his last one. (boring)
14. Max finished the homework faster than anyone else in the class. (fast)
15. He doesn’t look as happy as he used to. (happy)

12. Rút gọn các biểu thức sau: b.B=[(1/(1 - 2√x)) - 1]:[(1/(4x - 1)) + (1/(1 + 2√x )) với x>0; x # 1/4

Thu gọn biểu thức:

√[4√3 +2√(7-4√3)]