Passage FOUR Questions 21 to 25 are based on the following passage.
Lead deposits, which accumulated in soil and snow during the 1960's and 70's, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Clean Air Act has mandated unleaded gas use in the United States, the lead accumulation world-wide has decreased significantly.
A study published recently in the journal Nature shows that air-borne leaded gas emissions from the United States were the leading contributor to the high concentration of lead in the snow in Greenland. The new study is a result of the continued research led by Dr. Charles Boutron, an expert on the impact of heavy metals on the environment at the National Center for Scientific Research in France. A study by Dr. Boutron published in 1991 showed that lead levels in arctic(北极的) snow were declining.
In his new study, Dr. Boutron found the ratios of the different forms of lead in the leaded gasoline used in the United States were different from the ratios of European, Asian and Canadian gasolines and thus enabled scientists to differentiate ( 分区) the lead sources. The dominant lead ratio found in Greenland snow matched that found in gasoline from the United States.
In a study published in the journal Ambio, scientists found that lead levels in soil in the North-eastern United States had decreased markedly since the introduction of unleaded gasoline.
Many scientists had believed that the lead would stay in soil and snow for a longer period.
The authors of the Ambio study examined samples of the upper layers of soil taken from the same sites of 30 forest floors in New England, New York and Pennsylvania in 1980 and in 1990.
The forest environment processed and redistributed the lead faster than the scientists had expected.
Scientists say both studies demonstrate that certain parts of the ecosystem (生态系统 ) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute.
26. The study published in the journal Nature indicates that
A) lead deposits in arctic snow are on the increase
B) the Clean Air Act has not produced the desired results
C) the US is the major source of lead pollution in arctic snow
D) lead will stay in soil and snow longer than expected
27. Lead accumulation worldwide decreased significantly after the use of unleaded gas in the US
A) was introduced
B) was discouraged
C) was prohibited by law
D) was enforced by law
28. How did scientists discover the source of lead pollution in Greenland?
A) By analyzing the data published in journals like Nature and Ambio.
B) By studying the chemical elements of soil and snow in Northeastern America.
C) By comparing the chemical compositions of leaded gasoline used in various countries.
D) By observing the lead accumulations in different parts of the arctic area.
29. The authors of the Ambio study have found that
A) forests get rid of lead pollution faster than expected
B) lead deposits are widely distributed in the forests of the US
C) lead accumulations in forests are more difficult to deal with
D) the upper layers of soil in forests are easily polluted by lead emissions
30. It can be inferred from the last paragraph that scientists
A) lack sufficient means to combat lead pollution
B) still consider lead pollution a problem
Part III Vocabulary (20 minutes)
Directions: There are 30 incomplete sentences in this part. For each sentence there are four choices marked A), B), C) and D). Choose the ONE answer that best completes the sentence. Then mark the corresponding letter on the Answer Sheet with a single line through the centre.
31. Salaries for positions seem to be higher than for permanent ones.
32. Mrs. gmithwas so about everything that no servants could please her.
33. His temper and personalky show that he can become a soldier of the top
34. There has been a collision a number of cars on the main road to town.
35. Norman Davis will be remembered by many with not only as a great scholar but also as a most delightful and faithful friend.
36. Science and technology have in important ways to the improvement of agricultural production.
37. He never arrives on time and my is that he feels the meetings are useless.
38. Only those who can to lose their money should make high-risk investments.
39. Ten days ago the young man info~ed his boss of his intention to
40. Though she began her by singing in a local pop group,she is now a famous Hollywood movie star.
41. As he has our pratience,we’ll not wait for him any longer.
42. Tomorrow the mayor is to a group of Canadian businessmen on a tour of the city.
43. Most people agree that the present role of women has already affected U.S. society.
it has affected the traditional role of men.
A) Above all
B) In all
C) At most
D) At last
44. It is obvious that this new rule is applicable to everyone without
45. As one of the world's highest paid models, she had her face. for five million dollars
46. The machine looked like a large, ，old-fashioned typewriter.
47. Within two weeks of arrival, all foreigners had to with the local police
48. I'm enough to know it is going to be a very difficult situation to compete against three strong teams.
49, He found the media attention intolerable and decided to go abroad.
50, elephants are different from wild elephants in many aspects, including their tempers.
Part IV Cloze (15 minutes)
Directions: There are 20 blanks in the following passage. For each blank there are four choices marked A), B), C) and D) on the right side of the paper You should choose the ONE that best fits into the passage. Then mark the corresponding letter on the Answer Sheet with a single line through the centre.
Wise buying is a positive way in which you can make your money go further. The 61 go about purchasing an article or a service can actually 62 you money or can add 63 the cost.
Take the 64 example of a hairdryer. If you are buying a hairdryer, you might 65 you are making the 66 buy if you choose one 67 look you like and which is also the cheapest 68 price. But when you get it home you may find that it 69 twice as long as a more expensive 70 to dry your hair. The cost of the electricity plus the cost of your time could well 71 your hairdryer the most expensive one of all.
So what principles should you 72 when you go out shopping?
If you_ 73 your home, your car or any valuable 74 in excellent condition, you'll be saving money in the long 75 Before you buy a new 76 , talk to someone who owns one.If you can,use it or borrow it to check it suits your particular 77 .
Before you buy an expensive 78 ,or a service,do check the price and 79 is on offer. If possible, choose 80 three items or three estimates.
61. A) formL
63. A) to
65. A) convince
68. A) on
69. A) spends
70. A) mode
73. A) keep
74. A) products
75. A) interval
76. A) equipment
78. A) item
79. A) this
80. A) in
Part V Writing (30 minutes)
Directions: For this part, you are allowed 30 minutes to write a campaign speech in support of your election to the post of chairman of the student union. You should write at least 120 words following the outline given below in Chinese.
A Campaign Speech