学术英语2unit3答案

a.disappear f.mysteryb.powerful g.eventc.identify h.gapd.period i.accepte.publish j.existj Dinosaurs have all died out, but some animals that lived around the same time continue to (be present) in some form today.e My professor is going to (arrange to write and print) a book about astronomy and geology.c The scientists found some very old bones in the ground and were able to (recognize and name) them as the leg bones of a dinosaur.a When living conditions on Earth become very difficult, animals or plants sometimes (become impossible to find), and are gone forever.g The formation of the oceans was a major (thing that happened) in the history of the Earth.h There is about 100 million years between the appearance of the first dinosaurs and the appearance of the first flowers on Earth. That's a big (difference between two amounts or situations).d At a certain (time) in the history of the Earth, there were many dinosaurs.b Dinosaurs were big, (strong) animals, and most other animals were probably afraid of them.i It is hard for many people to (believe) that an asteroid could hit the Earth again.f Nobody knows why all the dinosaurs died; it is a (thing that is difficult to explain or understand).1. Sometimes objects from outer space collide with the Earth and cause a lot of damage.2. The volcano erupted, sending red hot lava down its slopes into the valley below.3. Most people don't think that there could be an asteroid collision with Earth, but scientists continue to do research about the possibility of this happening.4. There are many different species of animals on Earth—some eat plants, and some eat meat.5. When an animal or plant becomes completely extinct , there are no living animals or plants of its kind on Earth.6. One of the largest animals to ever walk the earth is the dinosaur .7. When a(n) mass extinction occurs, many types of animals die at the same time.8. Some people think that after a big asteroid hit Earth, many different kinds of animals died.9. Today, scientists are still concerned about the extinction of some rare species of animals.1. During the "Big Five" extinction events, dinosaurs werefalsethe only species that became extinct.2. The theory about the "Big Five" extinction events was firsttrue proposed in 1982.3. All scientists agree that the "Big Five" extinction eventsfalse happened.4. The "Big Five" extinction events are named for the speciesfalsethat became extinct.1. 20% of sea species became extinct.A. End Ordovician Extinction EventB. Late Devonian Extinction EventC. End Permian Extinction EventD. End Triassic Extinction EventE. End Cretaceous Extinction Event2. 50% of all species became extinct.A. End Ordovician Extinction EventB. Late Devonian Extinction EventC. End Permian Extinction EventD. End Triassic Extinction EventE. End Cretaceous Extinction Event3. 70% of all species became extinct.A. End Ordovician Extinction EventB. Late Devonian Extinction EventC. End Permian Extinction EventD. End Triassic Extinction EventE. End Cretaceous Extinction Event4. 70% of land species became extinct.A. End Ordovician Extinction EventB. Late Devonian Extinction EventC. End Permian Extinction EventD. End Triassic Extinction EventE. End Cretaceous Extinction Event5. Almost 100% of sea species became extinct.A. End Ordovician Extinction EventB. Late Devonian Extinction EventC. End Permian Extinction EventD. End Triassic Extinction EventE. End Cretaceous Extinction Event6. Second largest mass extinction occurred.A. End Ordovician Extinction EventB. Late Devonian Extinction EventC. End Permian Extinction EventD. End Triassic Extinction EventE. End Cretaceous Extinction Event7. It took 20 million years to happen.A. End Ordovician Extinction EventB. Late Devonian Extinction EventC. End Permian Extinction EventD. End Triassic Extinction EventE. End Cretaceous Extinction EventReading All of your answers are correct. Well done!1. The scientist was able to more closely predict when a meteorite might hit the Earth again, which was a great achievement .2. The Earth does not have a lot of craters , but I am not sure about other planets.3. In rocks on Earth, the lower layers are normally older than those above them.4. It is amazing that some animals, like crocodiles and sharks, have managed to live on Earth for such a long time.5. Experts disagree on the reasons why dinosaurs became extinct, so my professor explained all of the possible reasons to the class.6. In this part of the mountain, the different kinds of rock match different periods in history.7. A very large percentage of the plants and animals in the area died after the volcano erupted.8. New evidence has been found to support the theory that dinosaurs went extinct when an Ice Age began and the world became very cold.9. Some plants are very vulnerable to high temperatures, and they quickly die if it gets too hot.10. The change in weather was very sudden—one minute it was boiling hot, and the next it was freezing cold.1. Florida has a very hot climate , and it sometimes rains a lot there.2. Scientists think that all the dinosaurs on Earth were killed when some kind of terrible catastrophe happened.3. When the meteorite hit the earth, it made a giant hole in the ground.4. The effects of the volcanic eruption were catastrophic . It burned up everything in the area.5. The earth is surrounded by a layer of air called the atmosphere .6. There is evidence to support the theory that a few dinosaurs survived the mass extinction of their species.All of your answers are correct. Well done!1. The dinosaurs _______.A. disappeared under conditions that are not certainB. lived in only a few places on EarthC. were the largest animals that ever livedD. disappeared because of a sudden climate changeE. were the only species that died 65 million years ago2. Researchers discovered that _______.A. there is a layer of iridium in the rock near where dinosaurslivedB. there are large amounts of iridium in the rock layer all aroundC. the rock layer with iridium formed about 65 million years agoD. the rock layer has the same amount of iridium as meteoritesE. some dinosaur fossils have large amounts of iridium3. Researchers believe that _______.A. an asteroid hit the EarthB. dust from the asteroid went into the atmosphereC. the asteroid caused earthquakes and floodsD. the asteroid hit a lot of dinosaurs and killed themE. the iridium in the rocks came from an asteroid4. As a result of the asteroid hitting Earth, ______.A. dinosaurs had nothing to eatB. dust covered the plants and killed themC. dust in the atmosphere blocked the sunlightD. plants and animals diedE. the Earth became warmer1. The Chicxulub crater in Mexico provides evidence that an asteroidtruehit Earth.2. The Chicxulub crater was made by a 100-mile wide asteroid. false3. The asteroid that made the Chicxulub crater was stronger than atruenuclear bomb.4. Some scientists still think that volcanoes caused the masstrue extinction.5. It’s impossible to have dinosaur fossils that date from the periodfalseafter the mass extinction 65 million years ago.6. The mass extinction that killed the dinosaurs was probably notfalsecaused by a meteorite.7. Scientists can predict when the next mass extinction will happen. falseFor many years, one of the biggest mysteries in science has been how the dinosaurs disappearedThese amazing animals ruled Earth for 160 million years. They lived everywhere, on every continent. They were the largest and most powerful animals for a large part of the history of animal life on Earth. Compared with humans’two hundred thousand years or so, this is an amazing achievement. But, suddenly,about 65 million years ago , they all d ied. And it wasn’t just the dinosaurs—interestingly, more than 50 percent of all animal species onEarth also disappeared. This is very surprising, because there were very many different species of dinosaur, all suited to different climates and conditions . The normal causes of extinction, such as natural climate change , may explain why some species of dinosaur died out, but not all of them. As we will see, it seems likely that a major and sudden disaster caused their disappearance.1. So, what was this disaster ? In the past, scientists thought of many possible explanations. These included disease, earthquakes, volcanoes, or even changes in the magnetic field of Earth. Unfortunately, for a long time, there was nostrong evidence for any of them.2. Alvarez and his team were amazed to find that the layer of rock that matched the time of the dinosaurs’extinction 65 million years ago had a very large amount of something called iridium.3. In fact, there was 30 to 130 times more of this material than normal in this layer of rock. What amazed the Alvarez team was that this was about the same amount as the percentage of iridium in meteorites .4. Scientists can predict what might happen when a large asteroid hit Earth.The collision would send dust up into the atmosphere.5. Some say that the iridium layer is thicker in some places than others. No one can find a full explanation for this. People who disagree with the meteorite theory say that volcanoes could have produced the same result.6. Also, there is a small amount of evidence that not all dinosaurs died out. Archeologists have found dinosaur fossils from up to a million years later than the mass extinction.7. To conclude, current evidence seems to point to a(n) major catastrophe—most likely a meteorite.1. One reason the first paragraph of the passage is well-organized is becauseA. Each sentence explains something new about science.B. Each sentence uses different words to refer to a meteorite.C. Each sentence refers to a particular meteorite that fell to Earth.D. Each sentence contains referring words to give the reader informationThat glowing object turned out to be ameteorite.the fireball... they looked very different fromthe Australian soil…the pieces of the meteoriteThe most interesting thing about thefragments …the pieces of the meteoriteThe investigators reached a dramaticco nclusion…the scientists…made its way through Earth’satmosphere…the meteorite…this was a significant breakthrough. the conclusion that themeteorite had broken off fromVesta1. Which of the following sentences from the first paragraph contains a word that indicates the topic will be shifting?A. Scientists were able to identify the pieces of the meteorite because they looked very different from the Australian soil into which they fell.B. The most interesting thing about the fragments, however, was not their difference from Earth’s soil but their similarity to the known composition of a particular asteroid known as Vesta.C. The investigators concluded that the meteorite had broken off from Vesta and made its way through Earth’s atmosphere to land in Australia.D. Because the sources of most meteorites are never identified,this was a significant breakthrough.2. Which of the following will paragraph 2 of the selection most likelyexplain?A. the reasons the meteorite broke off from Vesta and fell to EarthB. the reaction of the people in Australia to the meteoritebreaking off from VestaC. the method the scientists used to determine that the meteoriteD. the qualifications of the scientists who studied the meteoritethat broke off from VestaListening1. The ____ of Australia is south of Asia.A. continentB. diameterC. geologyD. solar system2. The _____ of the Earth is 12,756.2 kilometers.A. solar systemB. continentC. geologyD. diameter3. The Earth is the only planet in the _____ that can support life.A. continentB. solar systemC. geologyD. diameter4. Shooting stars are comets that _____ up when they hit the Earth's atmosphere.A. hitB. burnC. improveD. motivate5. Many people are afraid of the damage that _____ can do to the world.A. diametersB. solar systemsC. nuclear weaponsD. continents6. As tools and research methods _____, scientists are finding out more and more about the Earth.A. improveB. hitC. burnD. motivate7. Hector was interested in rocks, so he studied _____ in college.A. nuclear weaponsB. diametersC. geologyD. solar systems8. Volcanoes are often dangerous, but _____, the volcano in my town hasn't done any serious damage.A. scarilyB. constantlyC. dangerouslyD. fortunately9. When people feel that they are in danger, it can _____ them to take action and save themselves.A. hitB. burnC. motivateD. improve10. When objects from outer space _____ the Earth, they can cause a lot of damage.A. hitB. passC. motivateD. improve1. The comet went flying through the sky over our heads, leaving atruetrail behind it.2. After the meteorite hit the building, it was completely destroyed,trueand it had to be rebuilt.3. The volcanic eruption caused a great deal of destruction in thefalsearea, and none of the plants, animals, or people who lived nearbywere hurt at all.4. When the meteorite hit the building, you could hear the explosiontruefrom miles away.5. When something explodes, it jumps high into the air and thenfalselands, still in one big piece.1. It is likely that a large asteroid will hit Earth again.A. trueB. false2. There are more asteroid craters on Earth than on the moon.A. trueB. false3. Earth's atmosphere causes most asteroids to burn up before they hitthe ground.A. trueB. false4. The surface of Earth is always moving.A. trueB. false5. Earth doesn't have craters, so we are safe from being hit by anasteroid.A. trueB. false6. Large asteroids have never passed close to Earth.A. trueB. false7. Scientists predict that an asteroid will cause a catastrophic event on Earth in the near future.A. trueB. false8. NASA is trying to destroy all the asteroids that pass close to Earth.A. trueB. false9. Scientists haven't figured out what to do if an asteroid comes towards Earth.A. trueB. false10. If a dangerous object is coming toward Earth, we need to decide what to do about it immediately.A. trueB. false7Asteroid craters have disappeared.3The asteroids burn up.1Earth has an atmosphere.5Earth's surface is constantly moving.4Most asteroids disappear before they hit the ground.6New mountains and seas are formed.2The atmosphere slows down the asteroids.It’s clear, therefore, that the lack of craters doesn’t mean we’re safe! Scientists predict that a large asteroid, as big as the one that probably killed the dinosaurs, should hit Earth, on average, once every 10million years. But it’s65 million years since the last one! Smaller asteroids are passing close to Earth all the time. Only in1989 , an asteroid around 1000 feet in diameter—that’sabout 300 meters—called 4581 Asclepius, passed through the point where Earth was just six hours before. A hit from it would have caused the largest explosion in history. On average, researchers say, an object big enough to cause catastrophicresults will hit Earth every 5000 years.Astronomers are already working on this. Since the late 1990 s, NASA has been conducting several surveys of space, the biggest of which is LINEAR. NASA aims to find 90 percent of all the near-Earth objects, in other words, NEOs, that are more than two thirds of a mile—1 kilometer—in diameter. So far, tens of thousands of them have been found—most of them, fortunately, too far away to be dangerous for now. Also, a couple of near-misses have been identified, although usually rather late—after the object has passed Earth. In 2002 , anobject 250 feet—about 80 meters—in diameter passed only 75000 miles—that'sabout 120000 kilometers—from Earth.So, why isn't Earth covered in craters, just like the Moon and some of the planets ? Well, there are two reasons . For one thing, Earth has an atmosphere but the Moon doesn't. Earth's atmosphere slows asteroids down, causing heat which burns off their outer layers . Again, you can see this process yourself. Have you ever seen shooting stars ? They are actually the remains of broken up comets It is the burning that we can see. Most are very small, so they burn up completely and disappear before they get close tothe ground .Another reason comes from geology. Earth’s surface is constantly moving—as you probably know, this is called the plate tectonic theory , and is the reason for earthquakes When plates collide with each other,Earth's surface gets pushed up. In this way, mountains or islands are formed. When the continents move apart, huge valleys and seas are created. Thus, a map of Earth from the dinosaur's time would’ve looked very, very different from now .You can easily see how craters disappear as the land changes shape.1. Which statement is the best summary of the passage?A. Scientists’ early beliefs ab out asteroids are supported bythe results of a study on a crater in Africa.B. Scientists have found that asteroids are made of the samechemicals and minerals.C. Scientists use a number of different methods to measure anasteroid’s age.D. Scientists have made important discoveries from studying a2. Why does the speaker say this: “There are two reasons the discoveries are important.”A. to change to a different themeB. to introduce the topics she will discussC. to end the presentationD. to suggest subjects to researchWriting1. an asteroid hit Earththe dinosaurs became extinctAfter an asteroid hit Earth, the dinosaurs became extinct2. a meteorite hit near Tunguskapeople saw a bright lightPeople saw a bright light after a meteorite hit near Tunguska and a meteorite hit near Tunguska .3. the asteroid hit Earththe collision sent dust up into the airWhen the asteroid hit Earth, the collision sent dust up into the air .4. an asteroid's outer layer burns offit enters Earth's atmosphereAn asteroid's outer layer burns off after it enters Earth's atmosphere .5. there were four other mass extinction eventsthe event that killed the dinosaursThere were four other mass extinction events before the event that killed the dinosaurs .6. earthquakes occurthe tectonic plates collideEarthquakes occur when the tectonic plates collide .7. a large asteroid hits Earth.it releases more energy than a nuclear bombWhen a large asteroid hits Earth, it releases more energy than a nuclear bomb .8. scientific explanations changesomeone discovers new informationScientific explanations change when someone discovers new information .9.the discovery of iridiumscientists weren't sure how the dinosaurs diedBefore scientists weren’t sure how the dinosaurs died, the discovery of iridium .1. Scientists predict that an asteroid will hit Earth in 2018.A. trueB. false2. The CelesTek Space Research Agency does research on Near-Earth Objects.A. trueB. false3. Objects the size of a car burn up in the atmosphere before they hit Earth.A. trueB. false4. An object the size of a car hits Earth every 1,000 years.A. trueB. false5. An object the size of a football field fell in Russia in the early 1900s.A. trueB. false6. An object big enough to cause a serious catastrophe hits Earth every few thousand years.A. trueB. false1. How did the dinosaurs become extinct? This is one of the biggest mysteries in science.2. At first, scientists thought dinosaurs died out because of earthquakes or volcanoes. Later , they discovered evidence that an asteroid hit the earth.3. Scientists believe that a large asteroid hit Earth 65 million years ago. This event led to the extinction of the dinosaurs.4. Scientists looked at layers of rock made 65 million years ago. They contain high levels of iridium.5. When the asteroid hit Earth, the dust from the collision caused plants and trees to die. In addition , the dust in the atmosphere made the climate much cooler.6. There is a chance that another asteroid could hit Earth. However , it may not happen for thousands of years.7. Scientists are surveying Near-Earth Objects in space. They are looking for any objects larger than one meter in diameter.8. There are many Near-Earth Objects in space. However , there is not much danger that many of them could hit Earth.9. A large object from space hit Earth near Tunguska, Russia in 1908. This was the last object to hit Earth and cause significant damage.4单元1. Actors sometimes _____ with experts like historians to find out more about the characters they are playing.A. actB. attemptC. consultD. escape2. Some people think that the _____ to good acting is to find out as much as you can about the character you are playing.A. keyB. theaterC. skillD. role3. He has great acting _____; he's played many different kinds of parts in his movies.A. skillsB. keysC. theatersD. settings4. He is very excited because he is going to _____ in a new play on Broadway next year.A. consultB. performC. relaxD. escape5. When people _____ in plays or movies, they often try to be as realistic as possible.A. attemptB. relaxC. actD. escape6. This _____ is very old, and many famous actors have worked here.A. performanceB. actingC. filmD. theater7. He became a _____ actor after he took acting classes for several years.A. successfulB. relaxingC. poorD. difficult8. Ann is going to _____ to play the part of Queen Victoria, but I think she is too young to play the part.A. performB. actC. attemptD. escape9. After a busy day at work, Janet was finally able to _____ in front of the TV.A. consultB. actC. attemptD. relax10. People watch TV and movies to _____ from their everyday lives.A. escapeB. actC. performD. consultAll of your answers are correct. Well done!1. The actor got a great part in a play in a theater on Broadway.2. It is very important for actors to use their imagination when they act.3. She played the role of Queen Elizabeth in the movie.4. There are several interesting characters in that movie, but I liked the little girl the best.5. Watching the movie, it was easy to imagine that we were in ancient Greece.6. The plot of that movie didn't make sense—I couldn't understand what was going on in the story at all.7. The setting of the book was an island in the Pacific Ocean.8. Actors usually try to make their performances as realistic as possible.9. In the movie, the writer created a very funny family, where the children acted like the parents and the parents acted like the children.3The president consults a PR expert.4The president films a false war.1The president gets involved in a scandal.5The president hopes that people will forget the scandal.2The president is afraid he will lose the presidential election.listeningC The actor did a lot of (getting ready for) playing the role of President Kennedy; he met with people who knew the president and read many books about him.F The actors are up on the (raised floor of the theater), and the play is about to begin.D The character's (feelings because of) the news that she had lost her job surprised me. I expected her to be much more upset about it.A The Oscar is probably the most famous (prize) that an actor can receive for his or her work.H I didn't enjoy the movie because it didn't seem very (real or true) to me—how could such an old man win a race at the Olympics?J Actors use their imagination (together) with their emotions to perform their roles.G The student asked what the word authenticity meant, so the acting teacher (explained) it.B Hundreds of students went to the (long talk) this afternoon because a famous actor was speaking about his new play.E The actor who played the father who had lost his child gave a performance that was very (full of feeling).I Often, the acting teacher talks about acting in general, but today she is going to (give special attention to and discuss in detail) how to play difficult roles.1. The actor thought it was very difficult to play the disabled old man because he couldn't imagine what it was like to have only one leg.2. The character Millicent was playing was from a different sector of society than she was, so to prepare for the role, she spent time in a poor area of the city.3. That movie is based on the life of Benjamin Franklin.4. The character had lost his arm in the war, but he didn't let his disability stop him from being successful in life.5. The director wanted to make sure his movie was as authentic as possible, so he visited old farms and copied the way they looked for his movie sets.6. He is planning to appear in a play called Hedda Gabler soon.7. The character of the artist had a great deal of authenticity because the actor who played him is an excellent painter.An actor's imagination is ______.a process of thinking about something he or she is currently experiencingbased on other actors' performancesbased on personal experiencebased on researchused during a performanceused to prepare for an acting roleused to write plays and movies1. Gene Blake would probably agree with this statement: “YouTruecan’t have a good performance without imagination”.2. An actor doesn't need to understand how a character he orFalseshe plays might feel in a certain situation.3. An actor should learn about the period of history when theTrue character lived.4. Most actors cannot play characters that are from aFalse different sector of society.5. Nothing about an actor's performance is based on truth. False6. Researching a character should involve reading andTrue spending time with people like the character.With the disabled character, there was a lifetime of frustration and of dealing with people’s reactions to the disability—experiences I just didn’t have. So, to fill this gap, I had to use imagination . Even though my character was an adult, I spent a lot of time thinking through, imagining, how common childhood experiences would be different because of the disability; how that would havea emotional effect on the adult me. Because of course, people are shaped by their experiences . And this hard work paid off—I won an award for the role. What a celebration we had after that! We were partying for days!But of course, personal experiences can be very, very useful for some roles . I played a London gang member once. Now, I’m not British, as you know, but I did have some experiences in my younger days with, shall we say, some of theless friendly people in New York. Some of these experiences helped meto understand what it feels like to be living on the edges of society. It wasn’t exactly the same, of course, and you’ll never have exactly thesame life experiences as your character . But, imagination is a way to fillthat gap , too.。