Số mol e cần dùng để khử 0.25 mol Fe₂O₃ thành Fe là bao nhiêu ?

Mark the letter A, B, C, or D to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions.

5. Becoming a super star performing on stage was my burning desire when I was a teenager.

A. well-known painter B. famous singer C. good writer D. famous composer

6. His latest single was released last month. Many people had been waiting for it.

A. produced B. finished C. launched D. composed

Mark the letter A, B, C, or D to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions.

7. She was given a prize for her achievement in classical and traditional music.

A. success B. feat C. failure D. accomplishment

8. A smartphone is too costly for him to even have a normal one.

A. economical B. expensive C. priceless D. valuable

Mark the letter A, B, C, or D to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions.

1. A. gloves B. says C. months D. sings

2. A. stopped B. based C. pushed D. pleased

Mark the letter A, B, C, or D to indicate the word that differs from the other three in the position of the primary stress in each of the following questions.

3. A. difficulty B. simplicity C. discovery D. commodity

4. A. engineer B. understand C. referee D. mechanic

Mark the letter A, B, C, or D to indicate the sentence that best combines each pair of sentences in the following questions.

47. Lan was busy last night, so she couldn’t join us.

A. If Lan wasn’t busy last night, she could join us.

B. If Lan was busy last night, she couldn’t join us.

C. If Lan hadn’t been busy last night, she could have joined us.

D. If Lan is busy tonight, she can join us.

48. He is introducing some new kinds of computers.

A. Some new kinds of computers are introduced.

B. Some new kinds of computers to be introduced.

C. Some new kinds of computers is being introduced.

D. Some new kinds of computers are being introduced

49. I like the picture which is hung on the wall.

A. I like the picture which I hung on the wall. B. The picture which I like is hung on the wall.

C. I like the picture it hung on the wall. D. The picture I like which is hung on the wall.

50. Offer your visitor a cup of tea.

A. Why don't you have a cup of tea? B. Could you have a cup of

C. Would you mind having a cup of tea? D. Will you have a cup of tea?

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions.

Computers are now an important part of human life. Without them, the modern world will stop: nobody will be able to travel, work, shop, watch TV, get money, or send messages.

However, together with computers come viruses - a kind of computer program. They move from one computer to another and damage the memory or other parts of the computer. Some viruses are difficult to stop; they can damage millions of computers in a very short time. The first virus called Brain appeared in 1986. In 1987, a more dangerous virus called Jerusalem appeared. It stayed in the computer and did nothing until the date was Friday 13th when it started to damage the computer's memory.

By the late 1990s, most computers were part of the e-mail and Internet systems. This meant virus programs could do a lot of destruction very quickly. The Melissa virus, for example, could move from one computer to another by e-mail - it automatically sent itself to every other email address in the address book.

In an effort to fight against viruses, programmers wrote antivirus software. Virus programmers are getting better all the time, but so is the antivirus software. However, a virus is always spread before a remedy takes action. People believe that one day a computer virus will bring the whole world to a stop for a few hours, which may paralyze many nations' government systems and cost the lives of many people who are traveling in a plane or undergoing an important operation.

42. The first virus appeared _________.

A.In 1986 B. In 1987 C. In 1990 D. On Friday 13th

43. Computer viruses became extremely dangerous _________.

A.on Friday 13th

B. when the first virus called Brain was created

C. when computers were connected to e-mail and Internet systems

D. in 1987

44. Which statement is TRUE about computer viruses?

A.The Melissa virus is part of the Internet system.

B. The virus Jerusalem is harmless because it did nothing.

C. A computer virus can kill people.

D. computer virus is a program.

45. A “remedy" (paragraph 4) refers to __________.

A.viruses B. programmers C. medicine D. antivirus software

46. The word "which" in the last paragraph refers to __________.

A.a computer virus created by people B. a computer virus

C. a few hours' stoppage caused by people D. the stoppage of the whole world caused by a computer virus

Read the following passage and mark the letter A, B, C, or D to indicate the correct word or phrase that best fits each of the numbered blank.

There can be no doubt (32) ____ that the Internet has made a huge difference to our lives. Parents are worried that children spend too much time playing on the Internet, hardly ever doing anything else in their spare time. Naturally, parents are (33) ____ to find out why the Internet is so attractive, and they want to know if it can be harmful for their children. Should parents worry if their children are spending that much time (34) ____ their computers?

Obviously, if children are bent over their computers for hours, (35) ____ in some game, instead of doing their homework, then soothing is wrong. Parents and children could decide how much use the child should (36) ____ of the Internet, and the child should give his or her (37) ____ that it won't interfere with homework. If the child is not holding to this arrangement, the parents can take more drastic steps. (38) ____ with a child's use of the Internet is not much different from negotiating any other sort of bargain about behavior.

Any parent who is seriously alarmed about a child's behavior should make an appointment to discuss the matter with a teacher. Spending time in front of the screen does not (39) ____ affect a child's performance at school. Even if a child is (40) ____ crazy about using the Internet, he or she is probably just (41) ____ through a phase, and in a few months there will be something else to worry about!

32. A. at least B. at all C. at length D. at most

33. A. reluctant B. concerned C. curious D. hopeful

34. A. watching B. glancing at C. glimpsing at D. staring at

35. A. puzzled B. absorbed C. interested D. occupied

36. A. cause B. take C. make D. create

37. A. word B. promise C. vow D. claim

38. A. Agreeing B. Dealing C. Talking D. Complaining

39. A. possibly B. unlikely C. probably D. necessarily

40. A. absolutely B. more C. enough D. a lot

41. A. going B. experiencing C. travelling D. walking