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in handy for the growth of buds in the early spring when leaves are not yet functioning. Once leaves begin photosynthesizing, they produce protein, but only mature leaves can “export” protein to the rest of the plant in the form of amino acids. 61. What is the main topic of the passage?

A. The relationship between a plant’s roots and its shoots. B. What can be learned by growing roots in isolation. C. How plants can be grown without roots.

D. What elements are necessary for the growth of plants.

62. The underlined word “themselves” in Paragraph 1 refers to___. A. plant physiologists B. solutions C. laboratory flasks D. roots 63. The scientists found what the isolated roots need is___.

A. quite natural B. sugar, minerals and vitamins C. some rare vitamins D. organic nitrogen compounds

64. Roots have the ability to___.

A. make proteins B. obtain fresh air C. produce inorganic nitrogen D. carry out activities without energy

65. According to the passage, what is ATP?

A. A biochemical process B. The tip of a root C. A chemical compound D. A type of plant cell

66. The underlined word “intact” in Paragraph 2 is closest in meaning to___. A. mature B. wild C. whole D. tiny 67. The use of the phrase “comes in handy” underlined in Paragraph 2 indicates that the process is___.

A. unavoidable B. predictable C. necessary D. successful

68. It can be inferred from the passage that, in the early spring, the buds of plants___.

A. “export” protein in the form of amino acids B. do not require water

C. have begun photosynthesizing

D. obtain organic compounds from the root

69. Which of the following best describes the organization of the passage? A. The results of two experiments are compared.

B. A generalization is made, and several examples of it are given. C. The findings of an experiment are explained.

D. A hypothesis is presented, and several means of proving it are suggested. 70. Where is this passage likely to be found?

A. A newsletter. B. A magazine C. A storybook D. A novel (3)

Natural flavorings and fragrances are often costly and limited in supply. For example, the vital ingredient in a rose fragrance is extracted from natural rose oil at a cost of thousands of dollars a pound; an identical synthetic substance can be made for 1% of this cost. Since the early twentieth century, success in reproducing these substances has created a new industry that today produces hundreds of artificial flavors and fragrances.

Some natural fragrances are easily synthesized; these include vanillin, the aromatic ingredient in vanilla, and benzaldehyde, the aromatic ingredient in wild cherries. Other fragrances, however, have dozens, even hundreds of components. Only recently has it been possible to separate and identify these ingredients by the use of gas chromatography and spectroscopy. Once the chemical identity is known, it is often possible to synthesize them. Nevertheless, some complex substances such as the aroma of fresh coffee, have still not been duplicated satisfactorily.

Many of the chemical compounds making up these synthetics are identical to those found in nature, and are as harmless or harmful as the natural substances. New products must be tested for safety, and when used in food, must be approved by the U.S. Food and Drug Administration.

The availability of synthetic flavors and fragrances has made possible a large variety of products, from inexpensive beverages to perfumed soap to used cars with applied “new car odor”.

71. From the passage we can learn that___.

A. natural flavorings and fragrances are not quite dear

B. the limitation of natural flavorings and fragrances is clear

C. the supply of natural flavorings and fragrances is adequate to meet the demand D. the cost of producing natural flavorings and fragrances is high 72. Which of the following is true according to the passage?

A. Natural rose fragrance is 100 times more expensive to produce than artificial rose fragrance. B. The most important ingredient in a rose fragrance is obtained from natural rose oil at a low cost.

C. A different synthetic substance can be made for 1% of the cost. D. Natural rose oil costs the same as its fragrances.

73. The industry of producing hundreds of artificial flavors and fragrances probably appeared in___.

A. 2000 B. 1953 C.1909 D.1810

74. According to the passage, all the following are easier to synthesize EXCEPT___. A. aromatic ingredient in vanilla B. vanilla

C. aromatic ingredient in wild cherry D. the flavor of flesh coffee

75. The underlined word “duplicated” in Paragraph 2 is closest in meaning to___. A. make double B. make a copy of

C. produce something equal to D. take from

76. Why does the author mention fresh coffee in Paragraph 2?

A. As an example of complex substances having not been duplicated satisfactorily. B. Because the coffee fragrance is hard to produce. C. To conclude the passage D. If spectroscopy is adopted.

77. ___, a substance can be synthesized.

A. Upon identifying the basic components of it B. Once chemically analyzed

C. When gas chromatography is used D. If spectroscopy is adopted

78. It can be inferred from the passage that___.

A. vanillin is easier to synthesize than benzaldehyde B. not all synthetic flavors are harmless

C. in general, the less components there are in fragrance, the harder it is to synthesize

D. synthesized substances must be tested for safety only if they are used in food 79. Which of the following is the best title for the passage? A. How to Synthesize Fragrances

B. Synthetic Substances Are Easy to Make C. Natural Flavorings and Fragrances D. Synthetic Flavors and Fragrances

80. Which of the following is NOT true according to the passage?

A. Synthetic fragrances can be used to make a used car smell like a new one. B. Synthetic flavors and fragrances have added to the varieties of products. C. Lemon soap is made out of some delicious lemon.

D. It is likely that a bottle of orange juice is synthesized. (4)

Some people associate migration with birds. Birds to travel vast distances, but mammals also migrate. An example is the caribou, reindeer that graze on the grassy slopes of northern Canada. When the weather turns cold, they travel south until spring. Their tracks are so well-worn that they are clearly visible from the air. Another migrating mammal is the Alaska fur seal. Theses seals breed only in the Pribilot Islands in the Bering Sea. The young are born in June and by September are strong enough to go with their mothers on a journey of over 3,000 miles. Together they swim down the Pacific Coast of North America. The females and young travel as far as southern California. The males do not journey so far. They swim only to the Gulf of Alaska. In the spring, males and females all return to the islands, and there the cycle begins again. Whales are among the greatest migrators of all. The humpback and blue whales migrate thousands of miles each year from the polar seas to the tropics. Wales eat huge quantities of plankton. These are most abundant in cold polar waters. In winter, the whales move to warm waters to breed and give birth to their young. 81. From the passage we can learn that___. A. people migrate like animals B. only birds migrate

C. the females fur seals migrate only to the Gulf of Alaska D. not all mammals migrate 82. The phrase “An example” underlined in Paragraph 1 refers to an example of a___. A. migratory mammal

B. place where animals migrate

C. migrating birds

D. person who associates migration with birds

83. All the mammals are mentioned as migrating ones EXCEPT___. A. caribou B. fin whale C. reindeer D. Alaska fur seal

84. Where can you see from the air the migration of the mammals? A. In the Pribilot Islands. B. In the Bering Sea C. In southern California D. In northern Canada 85. Which of the following is NOT true? A. Wales breed in winter.

B. Young whales are given birth in cold waters.

C. Alaska fur seals give birth to the young only in one area. D. Alaska fur seals are born in warm weather.

86. Together___ of Alaska fur seals swim down the Pacific Coast of North America. A. mothers and the young B. fathers and the young C. parents and the young D. seals and whales

87. Which of the following is NOT described inn the passage? A. Whales migrate to breed and give birth to their young. B. Whale-watching in Boston in summer is attracting. C. Seals breed in the north before migration. D. Reindeer feed on grass. 88. Whales live on___.

A. tiny plants and animals in the sea. B. the grassy slopes of northern Canada. C. their young in cold winter.

D. the abundant seafood in tropic waters.

89. How many kinds of migrating mammals are mentioned in the passage? A. Four B. Three C. Two D. One

90. What is the best title of the passage? A. Three Types of Whales B. Birds Migration

C. Mammals Also Migrate

D. Several Kinds of Migration

(5)

Electronic mail has become an extremely important and popular means of communication.

Te convenience and efficiency of electronic mail are threatened by the extremely rapid growth in the volume of unsolicited commercial electronic mail. Unsolicited commercial electronic mail is currently estimated to account for over half of all electronic mail traffic, up from an estimated 7 percent in 2001, and the volume continues to rise. Most of these messages are fraudulent or deceptive in one or more respects.

The receipt of unsolicited commercial electronic mail may result in costs to

recipients who cannot to refuse to accept such mail and who incur costs for the storage of such mail, or for the time spent accessing, reviewing, and discarding such mail, or for both. The receipt of a large number of unwanted messages also decreases the convenience of the electronic mail and creates a risk that anted electronic mail messages, both commercial and noncommercial, will be lost, overlooked, or discarded amidst the larger volume of unwanted messages, thus reducing the reliability and usefulness of electronic mail to the recipient. Some commercial electronic mail contains material that many recipients may consider vulgar or pornographic in nature. The growth in unsolicited commercial electronic mail imposes significant monetary costs on providers of Internet access services, businesses, and educational and nonprofit institutions that carry and receives such mail, as there is a finite volume of mail that such providers, businesses, and institutions can handle without further investment in infrastructure. Many senders of unsolicited commercial electronic mail purposefully disguise the source of such mail.

Many senders of unsolicited commercial electronic mail purposefully include misleading information in the messages’ subject lines in order to induce the recipients to view the messages. While some senders of commercial electronic mail messages provide simple and reliable ways for recipients to reject (or ‘opt-out’ of) receipt of commercial electronic mail from such senders in the future, other senders provide no such ‘opt-out’ mechanism, or refuse to honor the requests of recipients not to receive electronic mail from such senders in the future, or both. Many senders of bulks unsolicited commercial electronic mail use computer programs to gather large numbers of electronic mail addresses on an automated basis from Internet websites or online services where users must post their addresses in order to make full use of the website or service. The problems associated with the rapid growth and abuse of unsolicited commercial electronic mail cannot be solved by the government alone. The development and adoption of technological approaches and the pursuit of cooperative efforts with other countries will be necessary as well.

91. According to the passage, efficiency of e-mail is threatened by___. A. heavy e-mail traffic

B. fraudulent e-mail messages C. large volume of messages

D. increasing amount of unwanted e-mail

92. Which of the following is NOT true about unwanted e-mail? A. It costs money to receive them. B. It’s free to store them. C. It takes time to access them. D. It takes time to throw them away. 93. Unwanted e-mail may___.

A. cause companies to fail in business B. cause wanted e-mail messages to lose C. damage the credit of a company D. do good to a small company