全新版大学英语视听阅读4答案.docx

1、全新版大学英语视听阅读4答案Unit 1 The Perfect Swarm Unit 2 The Red Devils Unit 3 The Orient ExpressUnit 4 The Varied Cultures of China Unit 5 Afghanistans Heroic ArtistsUnit 6 Natachas Animal Rescue Unit 7 Firewalking Unit 8 Living in the Slow LaneUnit 9 Alternative Energy Unit 10 Mars on EarthGlossaryUnit 1This

2、 story is set in the central and western ., particularly in the states of Texas,Oklahoma, Kansas,Nebraska, North and South Dakota, and Wyoming as well as the Rocky Mountains.In the 1800s, the Rocky Mountain locust brought massive destruction to Western settlers. Then, the insects suddenly disappeare

3、d almost without a trace. Now scientists hope to find a reason for the locusts extinction. What caused the Rocky Mountain locust to disappear Where will the scientists find the answersI.Locusts! Read the paragraph. Then match each word with the correct definition.Many places in the world regularly e

4、xperience plagues of locusts that can devastate entire countries. Locusts move in huge swarms, invade entire regions, and usually consume everything in their path. One swarm of locusts containing trillions of individual insects can eat thousands of tons of vegetation a day. Locusts are one of the wo

5、rlds most destructive insects, but they themselves are sometimes destroyed. In the 1800s, for example, the Rocky Mountain locust mysteriously became extinct.1.plague _E_2.locust _G_3.devastate _C_4.swarm _E_5.trillion _A 6.vegetation _F 7.extinct _B_A.1,000,000,000,000B.no longer in existenceC.cause

6、 extreme damageD.any widespread cause of misery, suffering, or deathE.a large group, usually of insectsF.the plant covering an areaG.an insect noted for flying in large groups and destroying cropsII.The Rocky Mountain Locust Mystery. Read the paragraph. Then complete the definitions with the basic f

7、orm of the underlined words or phrases.Dr. Jeff Lockwood is an entomologist who is particularly interested in the disappearance of the Rocky Mountain locust. The species was mysteriously wiped out in the late 1800s and there arent many clues as to why it happened. By studying locust specimens under

8、a microscope and by taking DNA samples from the dead locusts, Lockwood aims to find out why the Rocky Mountain locust suddenly disappeared from Earth.1.a thing or fact that helps provide an answer to a question; evidence: clue2.a person who studies insects: entomologist3.an item that is an example o

9、f a larger group: specimen4.destroy completely; cause to no longer exist: wipe out5.a scientific instrument that uses lenses to make small objects appear larger: microscope6.the material that carries the genetic information in the cells of each living thing: DNA SUMMARYThe mystery of the Rocky Mount

10、ain locust has baffled scientists in North America for over 100 years. After locusts completely devastated many parts of the United States in 1875, the entire species vanished from the continent. Entomologist Jeff Lockwood is determined to solve this mystery. After traveling to the Rocky Mountains a

11、nd studying locusts frozen in glaciers, Lockwood begins to look at the mystery from a new angle. Warming upTeaching NOTES1.Show students some pictures of locusts from the reading passage or other sources you can find.2.Have students guess why the locusts in this video and the reading passage are cal

12、led the perfect swarm.3.Ask questions like “ Have you ever seen a locust ” and “ What do you know about locustsGrasshopperThere are hundreds of species of grasshoppers. These insects belong to the suborder Caelifera in the order Orthoptera, and have antennae that are almost always shorter than their

13、 bodies, and short ovipositors organsfor laying eggs. Normally females are larger than males. Males have a single unpaired plate at the end of the abdomen. The two pairs of valves (triangles) at the end of the female abdomen are used to dig in sand by the female grasshopper when laying eggs.Although

14、 they differ in many features, they are easily confused with another sub-order of Orthoptera, Ensifera. The main distinguishing elements are the number of segments in their antennae and structure of the ovipositor. The location of the tympana and modes of sound production are other distinguishing fe

15、atures. Ensiferans have antennae with at least 2024 segments, and Caeliferans have fewer.ButterflyLike other holometabolous species with a complete metamorphosis where the immature insects are entirely different from the mature stages, butterflies e cycle goes thlirfough four stages: egg, larva, pup

16、a and adult. Their wings are large, often brightly colored, and they have conspicuous, fluttering flight.Butterflies comprise the true butterflies, the skippers and the moth-butterflies. The very many other families within the order Lepidoptera are considered moths. Some butterflies migrate over lon

17、g distances. Some have formed symbiotic and parasitic relationships with social insects such as ants. Butterflies are important economically as agents of pollination. A few species are pests because they can damage agricultural crops or trees in their larval stages.Culturally, butterflies are featur

18、ed in the visual and literary arts.DragonflyA dragonfly is an insect characterized by big multifaceted eyes, two pairs of strong transparent wings, and an elongated body. Dragonflies and damselflies are similar in differ in the position of their wings which are held away from, and perpendicular to,

19、the body when at rest. Like any other insects, dragonflies possess six legs, but are not able to walk.Dragonflies usually eat flies, bees, ants, butterflies, and other small harmful insects, and are valuable as predators who help keep the equilibrium between beneficial insects and usually live aroun

20、d lakes, ponds, streams and wetlands because their larvae, known as “ nymphs” , are aquatic.CricketPartially related to grasshoppers, crickets are another group of insects with long antennae and flattened bodies. They have good vision and hearing. Their compound eyes enable them to see in several di

21、rections simultaneously. A large number of crickets do not fly because their wings are not fully developed, but lie across the back. Their ability to jump to great heights compensates for the lack of flying skills. Crickets normally live less than one year. In the spring, the nascent insect hatches

22、and looks like the adult, except for the wings. Only after shedding the skin several times do crickets develop new wings.Although not all kinds of crickets are pests, some species such as the black field cricket can affect crops and gardens. They can also attack dwellings in autumn. The pale green t

23、ree cricket can destroy twigs and berry canes.In some cultures, it is said that crickets bring good luck. Some people believe that all those who are fortunate enough to hear their songs are blessed. If a cricket lives in the house, it is treated with respect. They are placed in small cages and given

24、 food and water as the inhabitants of the house think that their existence brings good fortune.Watchingvideo SCRIPTs locusIt came overNarrator: Damage from swarms of locusts can reach disastrous proportions. A single swarm of desert locusts can consume over 70,000 metric tons of vegetation a day. Th

25、ere is, however, one continent that -free:North America.Interestingly enough, this wasn talways true. For hundreds of years, the Rocky Mountain locust was a common pest in the American West. Back in the mid-1800s, thousands of pioneers journeyed across the . in search of free land and new opportunit

26、ies. They settled on the frontier of the western states, and began to farm the land intensively, growing corn and other crops.Then, in 1875, out of nowhere, a rare combination of air currents, drought, and basic biology produced the right conditions for an unthinkable event, the worst storm ever rec

27、orded, the “ perfect swarm.horizon like a strange, dark cloud. Not millions, not billions, but trillions of insects, sweeping through the land like a living tornado. Those who saw the incredible event and survived never forgot what they witnessed.The swarm came together over the state of Texas,and s

28、oon moved quickly across the frontier in a huge destructive cloud that was nearly 3,000 kilometers long. The storm spread north towards North Dakota. The locusts eventually went as far west as the Rocky Mountains, leaving a path of devastation and destruction wherever they went.An account from one p

29、erson who observed the swarm described the locust storm. The locusts came down from the sky like hail. Frightened people ran screaming into their homes as the locusts claws dug into their skand hung upon their clothing. They heard sharp cracks as the insects came underfoot. The large locusts were ev

30、erywhere, looking with hungry eyes turning this way and that. Their bodies blocked the sun, bringing darkness along with the destruction.Crop damages were absolutely astonishing. If such destruction were to happen today it would cost an estimated US$116 billion, more than the most costly hurricane i

31、n American history. And then, something remarkable happened: the Rocky Mountain locust simply vanished.At the University of Wyoming, entomologist Dr. Jeff Lockwood has spent over a decade investigating why the Rocky Mountain locust disappeared.Dr. Jeff Lockwood, University of Wyoming: “ There were p

32、robably more locusts in the largest swarm than thereare stars in the Milky Way trillions. Not only is something of that scale and magnitude and power gone, but it s gone within a few years. It s nottraesmifewnedohuasdsaeries of earthquakes or tidal waves or forest fires.And so it doesn t make sense that it could ve gone extinct. There s no reason for it to have done so. Itmystery. ”Narrator: It asmystery that Lockwood is determined to solve. Whatever wiped out the Rocky Mountain locust changed American histor