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Read the following passage and choose the letter A, B, C orD to indicate the correct answer for each of the blanks. The ocean bottom - a region nearly 2.5 times greater than the total land area of Earth - is a vast frontier that even today is largely unexplored and uncharted. Until about a century ago, the deep-ocean floor was completely inaccessible, hidden beneath waters averaging over 3,600 meters deep. Totally without light and subjected to intense pressures hundreds of times greater than at the Earths surface, the deep-ocean bottom is a hostile environment to humans, in some ways as forbidding and remote as the void of outer space. Although researchers have taken samples of deep-ocean rocks and sediments for over a century, the first detailed global investigation of the ocean bottom did not actually start until 1968, with the beginning of the National Science Foundations Deep Sea Drilling Project (DSDP). Using techniques first developed for the offshore oil and gas industry, the DSDP’s drill ship, the Glomar Challenger, was able to maintain a steady position on the ocean’s surface and drill in very deep waters, extracting samples of sediments and rock from the ocean floor. The Glomar Challenger completed 96 voyages in a 15-year research program that ended in November 1983. During this time, the vessel logged 600,000 kilometers and took almost 20,000 core samples of seabed sediments and rocks at 624 drilling sites around the world. The Glomar challenger’s core samples have allowed geologists to reconstruct what the planet looked like hundreds of millions of years ago and to calculate what it will probably look like millions of years in the future. Today, largely on the strength of evidence gathered during the Glomar Challenger’s voyages, nearly all earth scientists agree on the theories of plate tectonics and continental drift that explain many of the geological processes that shape the Earth. The cores of sediment drilled by the Glomar Challenger have also yielded information critical to understanding the world’s past climates. Deep-ocean sediments provide a climatic record stretching back hundreds of millions of years, because they are largely isolated from the mechanical erosion and the intense chemical and biological activity that rapidly destroy much land-based evidence of past climates. This record has already provided insights into the patterns and causes of past climatic change - information that may be used to predict future climates. The author refers to the ocean bottom as a “frontier” because it_____________
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. There are many theories of aging, but virtually all fall into the category of being hypotheses with a minimum of supporting evidence. One viewpoint is that aging occurs as the body's organ systems become less efficient. Thus failures in the immune system, hormonal system, and nervous system could all produce characteristics that we associate with aging. Following a different vein, many current researchers are looking for evidence at the cellular and sub cellular level. It has been shown that cells such as human fibroblasts (generalized tissue cells) grown in culture divide only a limited number of times and then die. (Only cancer cells seem immortal in this respect). Fibroblast cells from an embryo divide more times than those taken from an adult. Thus some researchers believe that aging occurs at the cellular level and is part of the cell's genetic makeup. Any event that disturbs the cell's genetic machinery such as mutation, damaging chemicals in the cell's environment, or loss of genetic material, could cause cells to lose their ability to divide and thus bring on aging. Other theories of aging look at different processes. Chronological aging refers to the passage of time since birth and is usually measured in years. While chronological age can be useful in estimating the average status of a large group of people, it is a poor indicator of an individual person's status because there is a tremendous amount of variation from one individual to the next in regard to the rate at which biological age changes occur. For example, on the average, aging results in people losing much of their ability to perform strenuous activities, yet some elderly individuals are excellent marathon runners. Another type of aging is cosmetic aging, which consists of changes in outward appearance with advancing age. This includes changes in the body and changes in other aspects of a person's appearance, such as the style of hair and clothing, the type of eyeglasses, and the use of a hearing aid. Like chronological aging, it is frequently used to estimate the degree to which other types of aging have occurred. However, it is an inaccurate indicator for either purpose because of variation among individuals and because a person's appearance is affected by many factors that are not part of aging, including illness, poor nutrition, and exposure to sunlight What is the best title for this passage?
Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions from 35 to 42        Whether it's the melodic sound of an Eric Clapton solo or the growl of a heavy metal band, the electric guitar has influenced popular music and culture more than any other instrument. Rock's greatest musicians have always been closely identified with their guitars. But the instruments being designed for tomorrow's pop stars may look and sound rather different from today's familiar electric and acoustic guitars.        It is only sixty years since the electric guitar was invented. Since then there have been incredible changes to the technical design of the instrument. From what was once a rounded wooden box with a hole in the front, the guitar has evolved into the smooth solid body of the rock guitarist's "axe”. The most modern guitars are really computer-controlled synthesizers.        Adolph Rickenbacker's Electro String Company produced the first world's first electric guitar. It was made of wood and played on the user's lap. The first real breakthrough in design came in 1950 when Leo Fender, a California radio repairman, made the first solid-bodied electric guitar, the Fender Telecaster. Soon after the inventor Les Paul made the famous Gibson Les Paul, Fender launched his stylish Stratocaster two years later. These guitars became standard instruments against which newer guitar designs are measured.        All sorts of different materials have been used to make guitars. Acoustic guitars are made from wood, which gives a soft tone. Wood is also a popular material in electric guitar manufacture, but more modern materials such as glass and carbon fiber are also used. There have also been guitars with metal bodies and necks though these were never popular with players, who claim metal feels cold in the hand.        Plastics, on the other hand, have been more used in guitar bodies. A company that makes parts for the aerospace industry has begun to use a kind of fiberglass that was originally used in helicopter blades to make the bodies for its electric-acoustic instruments. Other makers have begun to experiment with graphite, which is ten times stiffer than wood but much lighter. It doesn't expand or contract as the temperature or humidity changes either. This makes it particularly suitable for guitar necks and for tennis rackets, for which it is also used.        As long as scientists and musicians work together harmoniously, the electric guitar will continue to benefit from technological innovations. But for all the efforts of the guitar companies' design engineers, managers and quality controllers, it's the musicians who finally make the instruments sing - and not necessarily in the way the guitar maker intended.   What is likely to change in the future?
Read the following passage and choose the letter A, B, C or D to indicate the correct answer to each of the following questions. Paul Watson is an environmental activist. He is a man who believes that he must do something, not just talk about doing something. Paul believes in protecting endangered animals, and he protects them in controversial ways. Some people think that Watson is a hero and admire him very much. Other people think that he is a criminal. On July 16th, 1979, Paul Watson and his crew were onhis ship, which is called the Sea Shepherd. Watson and the people who work on the Sea shepherd were hunting on the Atlantic Ocean near Portugal. However, they had a strange prey; instead of hunting for animals, their prey was a ship, the Sierra. The Sea shepherd found the Sierra, ran into it and sank it. As a result, the Sierra never returned to the sea. The Sea Shepherd, on the other hand, returned to its home in Canada. Paul Watson and his workers thought that they had been successful. The Sierra had been a whaling ship, which had operated illegally. The captain and crew of the Sierra did not obey any of the international laws that restrict whaling. Instead, they killed as many whales as they could, quickly cut off the meat, and froze it. Later, they sold the whale meat in countries where it is eaten. Paul Watson tried to persuade the international whaling commission to stop the Sierra. However, the commission did very little, and Paul became impatient. He decided to stop the Sierra and other whaling ships in any way that he could. He offered to pay $25,000 to anyone who sank any illegal whaling ship, and he sank the Sierra. He acted because he believes that the whales must be protected. Still, he acted without the approval of the government; therefore, his actions were controversial. Paul Watson is not the only environmental activist. Other men and women are also fighting to protect the Earth. Like Watson, they do not always have the approval of their governments, and like Watson, they have become impatient. Yet, because of their concern for the environment, they will act to protect it. (Adapted from “Eco fighters” by Eric Schwartz, OMNI) According to the reading, an environmental activist is someone who_____________.
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word for each of the blanks. Parents whose children show a special interest in a particular sport have a difficult decision to (33) _____________about their childrens career, should they allow their children to train to become top sportsmen and women? For many children it means starting very young and school work, going out with friends and other interests have to take second place. It’s very difficult to explain to a young child why he or she has to train for five hours a day, even at the weekend, when most of his or her friends are playing. Another problem is of course money. In many countries money for training is (34) _____________from the government for the very best young sportsmen and women. If this help cannot be given, it means that it is the parents that have to find the time and the money to support their child’s (35) _____________and sports clothes, transport to competitions, special equipment etc. can all be very expensive. Many parents are understandably concerned that it is dangerous to start serious training in a sport at an early age. Some doctors agree that young muscles may be damaged by training before they are properly developed. Professional trainers, (36) _____________, believe that it is only by starting young that you can reach the top as a successful sports person. What is clear is that very (37) _____________people reach the top and both parents and children should be prepared for failure even after many years of training.