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Text 3 To understand how astrology works, we should first take a quick look at the sky. Although the stars are at enormous distances, they do indeed give the impression of being affixed to the inner surface of a great hollow sphere surrounding the earth. Ancient people, in fact, literally believed in the existence of such a celestial sphere. As the earth spins on its axis, the celestial sphere appears to turn about us each day, pivoting at points on a line with the earth’s axis of rotation. This daily turning of the sphere carries the stars around the sky, causing most of them to rise and set, but they, and constellations they define, maintain fixed patterns on the sphere, just as the continent of Australia maintains its shape on a spinning globe of the earth. Thus the stars were called fixed stars. The motion of the sun along the ecliptic is, of course, merely a reflection of the revolution of the earth around the sun, but the ancients believed the earth was fixed and the sun had an independent motion of its own, eastward among the stars. The glare of sunlight hides the stars in daytime, but the ancients were aware that the stars were up there even at night, and the slow eastward motion of the sun around the sky, at the rate of about thirty degrees each month, caused different stars to be visible at night at different times of the year. The moon, revolving around the earth each month, also has an independent motion in the sky. The moon, however changes it position relatively rapidly. Although it appears to rise and Set each day, as does nearly everything else in the sky, we can see the moon changing position during as short an interval as an hour or so. The moon’s path around the earth lies nearly in the same plane as the earth’s path around the sun, so the moon is never seen very far from the ecliptic in the sky. There are five other objects visible to the naked eye that also appear to move in respect to the fixed background of stars on the celestial sphere. These are the planets Mercury, Venus, Mars, Jupiter, and Saturn. All of them revolve around the sun in nearly the same plane as the earth does. So they, like the moon, always appear near the ecliptic. Because we see the planets from the moving earth, however, they behave in a complicated way, with their apparent motions on the celestial sphere reflecting both their own independent motions around the sun and our motion as well. The ancient people believed that
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Scientists around the world are racing to learn how to rapidly diagnose, treat and stop the spread of a new, deadly disease. SARS — Severe Acute Respiratory Syndrome — was (1) for the first time in February 2003 in Hanoi, (2) since then has infected more than 1,600 people in 15 countries, killing 63. At this (3) , there are more questions than answers surrounding the disease.Symptoms start (4) a fever over 100.4 degrees F, chills, headache or body (5) . Within a week, the patient has a dry cough, which might (6) to shortness of breath. In 10% to 200% of cases, patients require (7) ventilation to breathe. About 3.5% die from the disease. Symptoms (8) begin in two to seven days, but some reports suggest it (9) take as long as 10 days. Scientists are close to (10) a lab test to diagnose SARS. In the meantime, it is diagnosed by its symptoms. There is no evidence (11) antibiotics or anti-viral medicines help, (12) doctors can offer only supportive care. Patients with SARS are kept in isolation to reduce the risk of (13) . Scientists aren’t sure yet, but some researchers think it’s a (14) discovered coronavirus, the family of viruses that cause some common colds.Most cases appear to have been passed (15) droplets expelled when infected patients cough or sneeze. Family members of infected people and medical workers who care for them have been most likely to (16) the illness. But recent developments in Hong Kong suggest that the (17) might spread through air, or that the virus might (18) for two to three hours on doorknobs or other (19) Health experts say it is (20) , though, that sharing an elevator briefly with an infected person would be enough to pass the virus. Read the following text, Choose the best word(s) for each numbered blank and mark [A], [B], [C] or [D] on ANSWER SHEET 1.（）
Dear Laura,It was certainly grand of you and Ted to come and see me off! I kown it wasn’t easy for you to get to the airport at such an early hour, so I appreciate it all the more.Flying over water can get dreadfully boring after the first few hours, and your book of detective stories came in very handy. It was sweet and thoughtful of you to think of it.The flight was uneventful and we arrived in Beijing on schedule time. Kate and Luke met me at the airport, and we went straight to their charming little house. I know I am going to love here; I’m living together with my sister and her husband!I’ll write to you again, Laura. In the meantime, my thanks to you and Ted for your many kindnesses to me---- and my love to you both, always! What present did Laura give Lily（）of detective stories.
Text 1 Every newborn baby is dealt a hand of cards which helps to determine how long he or she will be allowed to play the game of life. Good cards will help those who have them to have a long and healthy existence, while bad cards will bring to those who have them terrible diseases like high blood pressure and heart disease. Occasionally, cards are dealt out that doom their holders to an early death. In the past, people never knew exactly which cards they had been dealt. They could guess at the future only by looking at the kind of health problems experienced by their parents or grandparents. Genetic testing, which makes it possible to find dangerous genes, has changed all this. But, until recently, if you were tested positive for a bad gene you were not obliged to reveal this to anyone else except in a few extreme circumstances. This month, however, Britain became the first country in the world to allow life insurers to ask for test results. So far, approval has been given only for a test for a fatal brain disorder known as Huntington’s disease. But ten other tests (for seven diseases) are already in use and are awaiting similar approval. The independent body that gives approval, the Department of Health’s genetics and insurance committee, does not have to decide whether the use of genetic information in insurance is ethical. It must judge only whether the tests are reliable to insurers. In the case of Huntington’s disease the answer is clear-cut. People unlucky enough to have this gene will die early, and cost life insurers dearly. This is only the start. Clear-cut genetic answers, where a gene is simply and directly related to a person’s risk of death, are uncommon. More usually, a group of genes is associated with the risk of developing a common disease, dependent on the presence of other genetic or environmental factors. But, as tests improve, it will become possible to predict whether or not a particular individual is at risk. In the next few years researchers will discover more and more about the functions of individual genes and what health risks — or benefits — are associated with them. The function of genetic testing is
Text 1 Every newborn baby is dealt a hand of cards which helps to determine how long he or she will be allowed to play the game of life. Good cards will help those who have them to have a long and healthy existence, while bad cards will bring to those who have them terrible diseases like high blood pressure and heart disease. Occasionally, cards are dealt out that doom their holders to an early death. In the past, people never knew exactly which cards they had been dealt. They could guess at the future only by looking at the kind of health problems experienced by their parents or grandparents. Genetic testing, which makes it possible to find dangerous genes, has changed all this. But, until recently, if you were tested positive for a bad gene you were not obliged to reveal this to anyone else except in a few extreme circumstances. This month, however, Britain became the first country in the world to allow life insurers to ask for test results. So far, approval has been given only for a test for a fatal brain disorder known as Huntington’s disease. But ten other tests (for seven diseases) are already in use and are awaiting similar approval. The independent body that gives approval, the Department of Health’s genetics and insurance committee, does not have to decide whether the use of genetic information in insurance is ethical. It must judge only whether the tests are reliable to insurers. In the case of Huntington’s disease the answer is clear-cut. People unlucky enough to have this gene will die early, and cost life insurers dearly. This is only the start. Clear-cut genetic answers, where a gene is simply and directly related to a person’s risk of death, are uncommon. More usually, a group of genes is associated with the risk of developing a common disease, dependent on the presence of other genetic or environmental factors. But, as tests improve, it will become possible to predict whether or not a particular individual is at risk. In the next few years researchers will discover more and more about the functions of individual genes and what health risks — or benefits — are associated with them. What does the word “cards” (Line 1, Para. 1) refer to
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