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第一篇 How the First Stars in the Universe Came into Existence
Researchers believe that our universe began with the Big Bang（宇宙大爆炸）about 13 billion years ago, and that soon after that event, matter began to form as small dust grains and gases. How the first stars formed from this dust and gas has been a burning question for years, but a state-of-the-art computer simulation now offers the most detailed picture yet of how these first stars in the universe came into existence.
The composition of the early universe was quite different from that of today, and the physics that governed the early universe were also somewhat simpler. Dr. Naoki Yoshida and colleagues in Japan and the U. S. incorporated these conditions of the early universe, sometimes referred to as the “cosmic dark ages,” to simulate the formation of an astronomical object that would eventually shine its light into this darkness.
The result is a detailed description of the formation of a protostar（原恒星）— the early stage of a massive primordial（原始的）star of our universe — and the researchers’ computer simulation sets the bar for further investigation into the star formation process. The question of how the first stars evolved is so important because their formations and eventual explosions provided the seeds for subsequent stars to come into being.
According to their simulation, gravity acted on minute density variations in matter, gases, and the mysterious “dark matter” of the universe after the Big Bang in order to form this early stage of a star — a protostar with a mass of just one percent of our sun. The simulation reveals how pre-stellar（前恒星）gases would have actually evolved under the simpler physics of the early universe to form this protostar. Dr. Yoshida’s simulation also shows that the protostar would likely evolve into a massive star capable of synthesizing（合成）heavy elements, not just in later generations of stars, but soon after the Big Bang.
Their simulation of the birth of a protostar in the early universe signifies a key step toward the ambitious goal of piecing together the formation of an entire primordial star and of predicting the mass and properties of these first stars of the universe. More powerful computers, more physical data, and an even larger range will be needed for further calculations and simulations, but these researchers hope to eventually extend this simulation to the point of nuclear reaction initiation — when a stellar（星球的）object becomes a true star.
31．According to the first two paragraphs, the early universe
A．was governed by simpler physics.
B．got fewer stars shinning in it.
C．started over 13 billion years ago.
D．was composed in a way similar to that of today.
32．What does the state-of-the-art computer simulation tell us about?
A．How the Big Bang occurred about 13 billion years ago.
B．How “cosmic dark ages” came into existence.
C．How dust grains and gases were formed after the Big Bang.
D．How the first stars came into being after the Big Bang.
33．The phrase “an astronomical object” in paragraph 2 refers to
A．cosmic dark ages.
B．dust and gas.
C．a protostar.
D．the early universe.
34．According to paragraph 4, which of the following is NOT true about a protostar?
A．It developed into a massive star during the Big Bang.
B．It evolved from pre-stellar gases.
C．It was able to integrate heavy elements when evolving into a massive star.
D．It had a mass of one percent of the sun.
35．According to the last paragraph, all of the following are the goals of the simulation project EXCEPT
A．to know more about the mass and properties of the first stars of the universe.
B．to simulate the process of how the early universe began.
C．to apply the simulation to the study of nuclear reaction initiation.
D．to discover the truth about the formation of a protostar.
第二篇 The Iceman
On a September day in 1991, two Germans were climbing the mountains between Austria and Italy. High up on a mountain pass, they found the body of a man lying on the ice. At that height (10,499 feet, or 3,200 meters), the ice is usually permanent, but 1991 had been an especially warm year. The mountain ice had melted more than usual and so the body had come to the surface.
It was lying face downward. The skeleton（骨架）was in perfect condition, except for a wound in the head. There was still skin on the bones and the remains of some clothes. The hands were still holding the wooden handle of an ax and on the feet there were very simple leather and cloth boots. Nearby was a pair of gloves made of tree bark（树皮）and a holder for arrows.
Who was this man? How and when had he died? Everybody had a different answer to these questions. Some people thought that it was from this century, perhaps the body of a soldier who died in World War I. since several soldiers had already been found in the area. A Swiss woman believed it might lie her father, who had died in those mountains twenty years before and whose body had never been found. The scientists who rushed to look at the body thought it was probably much older, maybe even a thousand years old.
With modern dating techniques, the scientists soon learned that the Iceman was about 5,300 years old. Born in about 3300 B.C．, he lived during the Bronze Age in Europe. At first scientists thought he was probably a hunter who had died from an accident in the high mountains. More recent evidence, however, tells a different story. A new kind of X-ray shows an arrowhead still stuck in his shoulder. It left only a tiny hole in his skin, but it caused internal damage and bleeding. He almost certainly died from this wound, and not from the wound on the back of his head. This means that he was probably in some kind of a battle. It may have been part of a larger war, or he may have been fighting bandits. He may even have been a bandit himself.
By studying his clothes and tools, scientists have already learned a great deal from the Iceman a- bout the times he lived in. We may never know the full story of how he died, but he has given us important clues to the history of those distant times.
41．The body of the Iceman was found in the mountains mainly because
A．two Germans were climbing the mountains.
B．the melted ice made him visible.
C．he was lying on the ice.
D．he was just on a mountain pass.
42．What can be inferred from paragraph 2?
A．The Iceman was killed while working.
B．The Iceman could have died from the wound in the head.
C．The Iceman lived a poor life.
D．The Iceman was struck dead from behind.
43．All the following are assumptions once made about the Iceman EXCEPT
A．he was a soldier in World War I.
B．he was a Swiss woman’s long-lost father.
C．he was born about a thousand years ago.
D．he came from Italy.
44．The scientists made the deduction that the Iceman
A．was probably in some kind of a battle.
B．was hit in the shoulder by an arrowhead.
C．had got a wound on the back of his head.
D．had a tiny hole in his skin causing his death.
45．The word “bandits” in paragraph 4 could he best replaced by
A．soldiers.
B．hunters.
C．shooters.
D．robbers.
第三篇 Scientists Make Sweet Discovery
Good news for chocoholics: the treat preferred by millions all over the world is good for you, according to American researchers at the University of California. Chocolate contains substances called flavonoids（类黄酮）that can help maintain a healthy heart and good circulation. The researchers have discovered that cocoa acts like aspirin and that eating a bar of chocolate once in a while may contribute to a healthy diet. Chocolate has also been shown to release endorphins（内啡肽）in the body: these chemicals help to reduce pain and stress and make you feel happy.
But who first discovered this wonderful way of keeping healthy? The Olmec Indians of Mexico and Central America were the first to grow cocoa beans, in about 1500 B.C. and the Mayas were drinking unsweetened cocoa hundreds of years before it became fashionable in Europe. The word chocolate comes from the Nahuatl word xocolali, which means “bitter water”.
In 1544, a delegation of Mayan nobles visited Philip of Spain and gave him jars of cocoa as a gift. Cocoa soon became fashionable in Spain and Portugal. The Spanish were the first to add sugar to their Cocoa drink. In the 17th century, chocolate was becoming fashionable with the middle-classes, not only as a drink but also as a medicine.
By the middle of the century, solid chocolate was becoming familiar. In 1753, a Swedish scientist renamed cocoa theobroma or “food for the gods”. In 1765, James Baker and John Hanan opened the first chocolate mill in the United States, introducing chocolate to the average citizen. In 1876, in Switzerland, Daniel Peter had the idea of adding milk in the chocolate. Making process and produced the first milk chocolate.
Since then, chocolate has grown enormously in popularity. One of the biggest chocolate-eating nations is Britain where the average man, woman, and child eats nine kilos of chocolate a year! In fact, chocolate is the number one comfort food and there are more “chocoholics” in Britain than anywhere else in the world. Researchers warn that although chocolate is good for you, it should be eaten in small quantities — and with no added milk.
41．Why is chocolate good for heart and circulation?
A．It reduces pain and stress.
B．It contains substances called flavonoids.
C．It releases endorphins in human body.
D．It acts like aspirin to protect heart.
42．When cocoa was first introduced into Europe, it soon became fashionable
A．as a drink.
B．as a gift.
C．as food.
D．as a medicine.
43．What did James Baker and John Hanan do about chocolate?
A．They produced the first milk chocolate.
B．They introduced chocolate to Europe.
C．They added sugar to make chocolate bars.
D．They made chocolate accessible to the average man.
44．Which of the following statements is NOT true according to the passage?
A．Chocolate contains substances that make people feel happy.
B．Chocolate is good for health if it is eaten with added milk.
C．Eating chocolate occasionally contributes to a healthy diet.
D．Chocolate is loved by millions of people worldwide.
45．What is the author’s tone about eating chocolate?
A．Ambiguous.
B．Negative.
C．Positive.
D．Humorous.
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