题目内容
Part A
Directions: Read the following three texts. Answer the questions on each text by choosing A, B, C or D. Mark your answers on ANSWER SHEET 1.
Why were the Wright brothers able to succeed in an effort at which so many others had failed？ Many explanations have been mentioned, but three reasons are most often cited. First, they were a team. Both men worked congenially and cooperatively, talked incessantly about the possibility of manned flight, and served as a conscious source of inspiration and encouragement to each other.
Both were glider pilots. Unlike some other engineers who experimented with the theories of flight, they experienced the practical aspects of aerodynamics by building and flying in kites and gliders. They had realized from their experiments that the most serious challenge in manned flight would be stabilizing and maneuvering the aircraft once it was airborne. While others concentrated their efforts on the problem of achieving lift for take-off, they were focusing on developing a three axis control for guiding their aircraft.
In addition, the Wright brothers had designed more effective wings for the airplane than had been previously engineered. Using a wind tunnel, they tested more than two hundred different wing designs, recording the effects of slight variations in shape on the pressure of air on the wings. The data from theses experiments allowed the Wright brothers to construct a superior wing for their air craft. In spite of these advantages, however, the Wright brothers might not have succeeded had they not been born at precisely the opportune moment in history. Attempts to achieve manned flight in the early nineteenth century were doomed because the steam engines that powered the aircrafts were so heavy in proportion to the power that they produced. But by rite end of the nineteenth century, when the brothers were experimenting with engineering options, a relatively light internal combustion engine had already been invented, and they were able to bring the ratio of weight to power within acceptable limits for flight.
What is the passage mainly talking about？
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Since the early 1980s, scientists have revealed some 40 human genes involved in cancer. These genes are essential for normal growth, but can be subverted to cause a tumor.
Dr. Jorge Yunis of the University of Minnesota Medical School in Minneapolis has found that 70 percent of oncogenes, or cancer-causing genes, are located near inherited weak points on chromosomes(染色体). Varying from individual to individual, vulnerable to chemical carcinogens(致癌剂), X rays and other cancer-inducing agents.
"If a chromosome snaps apart in the immediate vicinity of an oncogene," says Yunis, "normal genetic control mechanisms could break down and the stage would be set for the formation of cancer." Younis has shown that such a sequence occurs at the beginning of numerous leukemias (白血病), lymphomas(淋巴瘤) and some tumors of the lung, colon(结肠) and breast.
Yunis and other investigators have found that petroleum-based products--notably pesticides and insecticides-damage specific sites on at least two of the 23 pairs of human chromosomes that carry genetic information. Similarly, tobacco smoke tends to attack a part of another chromosome.
From paragraph 1, we know that some 40 genes involving in cancer are ______. ()
Let us take an obvious example. Man, even five hundred years ago, was shorter than he is today. Now, on average, men are about three inches taller. Five hundred years is a relatively short period of time, so we may assume that man will continue to grow taller. Again, in the modern world we use our brains a great deal. Even so, we still make use of only about 20% of the brain's capacity. As time goes on, however, we shall have to use our brains more and more, and eventually we shall need larger ones! This is likely to bring about a physical change too: the head, in particular the forehead, will grow larger.
Nowadays our eyes are in constant use. In fact, we use them so much that very often they become weaker and we have to wear glasses. But over very long period of time it is likely that man's eyes will grow stronger.
On the other hand, we tend to make less use of our arms and legs. These, as a result, are likely to grow weaker. At the same time, however, our fingers will grow more sensitive because they are used a great deal in modern life.
But what about hair？ This will probably disappear from the body altogether in course of time because it does not serve a useful purpose any longer. In the future, then, both sexes are likely to be bald.
Perhaps all this gives the impression that future man will not be a very attractive creature to look at! This may well be true. All the same, in spite of all these changes, future man will still have a lot in common with us. He will still be a human being, with thoughts and emotions similar to our own.
The passage mainly tells us that ______.
Many teachers believe that the responsibilities for learning lie with the student.【C1】______a long reading assignment is given, instructors expect students to be familiar with the【C2】______in the reading even if they don't discuss it in class or take an exam. The【C3】______student is considered to be【C4】______who is motivated to learn for the sake of【C5】______, not the one interested only in getting high grades. Sometimes homework is returned【C6】______brief written comments but without a grade. Even if a grade is not given, the student is【C7】______for learning the material assigned. When research is【C8】______, the professor expects the student to take it actively and to complete it with【C9】______guidance. It is the【C10】______responsibility to find books, magazines, and articles in the library. Professors do not have the time to explain【C11】______a university library works; they expect students,【C12】______graduate students, to be able to exhaust the reference【C13】______in the library. Professors will help students who need it, but【C14】______that their students should not be【C15】______dependent on them. In the United States, professors have many other duties【C16】______teaching, such as administrative or research work.【C17】______, the time that a professor can spend with a student outside of class is【C18】______If a student has problems with classroom work, the student should either【C19】______a professor during office hours【C20】______make an appointment.
【C1】
Part A
Directions: You will hear 10 short dialogues. For each dialogue, there is one question and four possible answers. Choose the correct answer ― A, B, C or D, and mark it in your test booklet. You will have 15 seconds to answer the question and you will hear each dialogue ONLY ONCE.
听力原文：W: Tom, there is a new movie in town. We must go and see it.
M: OK, but let's have breakfast first, I'm quite hungry.
W: OK, hurry up.
What does the man propose to do first？
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