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 Express

Unit 4 The Varied Cultures of China Unit 5 Afghanistan's Heroic Artists

Unit 6 Natacha's Animal Rescue Unit 7 Firewalking Unit 8 Living in the Slow Lane

Unit 9 Alternative Energy Unit 10 Mars on Earth

Glossary

Unit 1

This 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 disappeared almost without a trace. Now scientists hope to find a reason for the locust's extinction. What caused the Rocky Mountain locust to disappear Where will the scientists find the answers

I. Locusts! Read the paragraph. Then match each word with the correct definition.

Many places in the world regularly experience 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 inpidual insects can eat thousands of tons of vegetation a day. Locusts are one of the world's 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. 1,000,000,000,000

B. no longer in existence

C. cause extreme damage

D. any widespread cause of misery, suffering, or death

E. a large group, usually of insects

F. the plant covering an area

G. an insect noted for flying in large groups and destroying crops

II. The Rocky Mountain Locust Mystery. Read the paragraph. Then complete the definitions with the basic form 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 aren't many clues as to why it happened. By studying locust specimens under 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: clue

2. a person who studies insects: entomologist

3. an item that is an example of a larger group: specimen

4. destroy completely; cause to no longer exist: wipe out

5. a scientific instrument that uses lenses to make small objects appear larger: microscope

6. the material that carries the genetic information in the cells of each living thing: DNA SUMMARY

The mystery of the Rocky Mountain 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 and studying locusts frozen in glaciers, Lockwood begins to look at the mystery from a new angle. Warming up Teaching NOTES

1. 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 called the perfect swarm.

3. Ask questions like “ Have you ever seen a locust ” and “ What do you know about locusts Grasshopper

There 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 bodies, and short ovipositors —organs

for 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 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 features. Ensiferans have antennae with at least 20—24

segments, and Caeliferans have fewer.

Butterfly

Like other holometabolous species with a complete metamorphosis where the immature insects are entirely different from the mature stages, butterflies e cycle goe 's thlirfough four stages: egg, larva, pupa 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 long 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 featured in the visual and literary arts.

Dragonfly

A 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, 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 around lakes, ponds, streams and wetlands because their larvae, known as “ nymphs ” , are aquatic.

Cricket

Partially 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 directions 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 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 tree 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 food and water as the inhabitants of the house think that their existence brings good fortune.

Watching

video SCRIPT

Narrator: 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. There 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 opportunities. 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 recorded, 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 soon 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 person 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 sk and hung upon their clothing. They heard sharp cracks as the insects came underfoot. The large locusts were everywhere,

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 in American history. And then, something remarkable happened: the Rocky Mountain locust simply vanished.

s locus It came over

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 probably more locusts in the largest swarm than there

are 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. It mystery. ”

Narrator: It 'asmystery that Lockwood is determined to solve. Whatever wiped out the Rocky Mountain locust changed American history. Exactly what could have destroyed a plague nearly 3,000 kilometers long Lockwood is on the case. He starts the investigation with the victim itself. Unfortunately, very few locust specimens exist, and those that do are often in bad condition. Dr. Lockwood: “ So what we have is a body of evidence of the victim in its dying moments, alright, but we don know what the life of the victim looked like when it was flourishing. The next opportunity we have for a major set of clues is locked up in the ice of the glaciers of the Rocky Mountains. ”

Narrator: Lockwood is headed to Knife Point Glacier, Wyoming, not far from Yellowstone National Park. For centuries, strong winds would sweep swarms of locusts high into the mountains, where they would freeze to death.

Dr. Lockwood: “ These glaciers serve as both traps and sort of icy tombs for the Rocky Mountain locust. Were we looking at a long, slow death, or were we looking at a sudden demise ”

Narrator: By extracting DNA samples from specimens frozen over a period of time, Lockwood may be able to specify exactly what caused the extinction of the insects. The good news for the expedition is that there could be locust specimens anywhere, but the bad news is that “ anywhere ” includes thousands of square meters covered with snow and ice. Then, on one of the steeper parts of the mountain, Lockwood sees something.

Dr. Lockwood: “ Check it out! ”

Lockwood' s Colleague: “ A whole body ”

Dr. Lockwood: “ It looks like it. ”

Lockwood' s Colleague: “ Head, thorax, and abdomen ”

Dr. Lockwood: “ Look, you can see the wings. ”

Narrator: Lockwood will take the locusts back to his laboratory to examine them more closely. If they right species, they could help solve one of the greatest extinction mysteries of our time.

Dr. Lockwood: “ To get my hands on the body, in terms of this murder mystery, was critically important.

Narrator: A look under the microscope reveals the signs.

Dr. Lockwood: “ At that moment, I knew that we had the Rocky Mountain locust. ”

Narrator: It ' s an exact match. They 're the same species of locusts that once devastated the American plains. Lockwood' s study of the Rocky Mountain locust has told him more and more about this odd insect. They seem to have split personalities. On one hand, as members of the grasshopper family, they ' re generally shy and remai alone. But when annoyed in just the right way, the once gentle locust changes completely into some kind of destructive monster. They change color and their wings and legs grow longer. Eventually, they become more aggressive and swarm, whereby they become a kind of living, breathing weapon of mass destruction.

Dr. Lockwood: “ Nobody' s in charge. There 's no leader, there 's nobody out in front. ”

Narrator: Back in the laboratory, the locusts are revealing their secrets. The DNA test results are back and they ' ve indicated one certain fact: the Rocky Mountain locust didn ' t decline over a long period of time.

Dr. Lockwood: “It was not sort of a death by old age. In fact, what we ' re looking at is a very sudden sort of out of the blue ' disappearance. There ' s nothing in the genetic course of this species that would lead us to believe that it was in its last days. ”

Narrator: Some other force must have been responsible for destroying the plague, and Lockwood is determined to find it.

Dr. Lockwood: “ I began to realize that we ' ve been looking at the wrong scale. If we want to find out perhaps what eliminated the Rocky Mountain locust, what we should be looking for is what was happening to the species at the time of its weakest link. ”

Narrator: Now, after years of research, Lockwood may finally be able to solve the mystery of why the Rocky Mountain locust disappeared. It turns out that the Rocky Mountain locust gathered in one particular region to lay its eggs. In the 1800s, that region was in the river valleys of the Rocky Mountains.

Dr. Lockwood: “ It turned out that agriculture was booming in these river valleys in the late 1800s.

Narrator: The gold and silver industries were booming as well. The major nesting area of the rocky Mountain locust had become

a busy and overcrowded place; therefore, conditions there would certainly have had an effect on any species.

Dr. Lockwood: “ Thekiller of the Rocky Mountain locust turns out to be us. The pioneer agriculturalist of the Rocky Mountain West in the late 1800s is the killer of the Rocky Mountain locust. ”

Narrator: As farms appeared in the river valleys to feed the miners, the farmers plowed up the fields and stamped out the delicate eggs that had been laid by the great swarm. By not allowing the eggs to mature into full-grown locusts, the species was entirely destroyed at its weakest—when the insects were just eggs. The only extinction of a pest species in agricultural history was in fact an accident.

Teaching notes

I. 1. Give students time to go through the statements.

2. Play the video.

3. Elicit the answers from students.

4. Have students discuss why the statements are true or false.

II. 1. Allow students some time to predict the answers.

2. Play the video.

3. Elicit the answers from students.

4. Have students summarize the main idea of this part.

III. 1. Explain how to conduct an interview.

2. Have students read the useful expressions.

3. Put students into pairs and have them discuss the interview questions and answers.

4. Have some pairs role-play their interviews to the class.

5. Give students some comments and suggestions for improvement.

Word bank

1. disastrous adj. causing great damage

A disastrous fire swept through the factory.

He made a disastrous mistake.

2. combination n. a number of separate things or people that are combined to form a single unit

or whole

A combination of drought and locusts forced people to leave their hometown.

3. destructive adj. causing great and irreparable damage

The storm could be destructive to the crops.

Useful expressions

Expressing surprise

* Oh, my!

* Incredible!

* Unbelievable!

* What a surprise!

* How could it be

* I couldn ' t believe my eyes.

Teaching notes

I. 1. Have students read the statements to get familiar with the ideas.

2. Play the video.

3. Elicit the answers from students.

II. 1. Give students time to predict the answers.

2. Play the video.

3. Elicit the answers from students.

III. 1. Have students read the useful expressions.

2. Put students into pairs and have them prepare the explanations.

3. Have some pairs present their explanations to the class.

4. Give students some comments and suggestions for improvement.

Word bank

1. investigate vt. try to find more information about

If you hear such a rumor, investigate it first.

It ' s not easy to investigate such a mysterious case.

2. tremendous adj. very great in size, amount or degree

There was a tremendous series of forest fires. He inherited a tremendous amount of money from his uncle.

3. specimen n. an inpidual animal, plant, etc. used as an example of its species or type for scientific study or display

They are in search of a special specimen of butterfly.

There are many specimens of copper ore in the lab.

Useful expressions Expressing determination

* I have decided to...

* I ' ve made up my mind to...

* He was determined to...

Teaching notes

I. 1. Give students time to predict the answers.

2. Play the video.

3. Elicit the answers from students.

4. Have them retell the activities carried out by Dr. Jeff Lockwood.

II. 1. Give students time to predict the answers.

2. Play the video.

3. Elicit the answers from students.

4. Have students ask and answer these questions in pairs.

III. 1. Have students repeat each sentence after it is spoken twice and then write the sentences.

2. Have students listen again, and mark the word stress on content words with a stress mark ().

3. Have students listen to each sentence and draw an upward arrow for rising intonation, or a downward arrow for falling intonation.

4. Have students listen again and draw a curved line to mark any words that are linked or blended together.

5. Have students practice reading the sentences till they can say them using appropriate intonation and stress pattern. Word bank

1. reveal vt. show or allow (something previously hidden) to be seen

He has successfully revealed the exact reason.

The DNA analysis reveals everything.

2. aggressive adj. always ready to quarrel or attack

The grasshopper turned out to be very aggressive.

The aggressive animal attacks anything that it meets.

3. eliminate vt. remove or get rid of completely

The government tried its best to eliminate poverty.

Teaching notes

I. 1. Give students time to predict the answers.

2. Play the video.

3. Elicit the answers from students.

II. 1. Give students time to predict the answers.

2. Play the video.

3. Elicit the answers from students.

III. 1. Have students read the useful expressions.

2. Put students into pairs and have them discuss the reasons, make comments and express their feelings.

3. Have some pairs present their discussion results to the class.

4. Give students some comments and suggestions for improvement.

Word bank

1. turn out happen to be or be found to be

It turns out that it's human beings who eliminated the Rocky Mountain locust.

She turns out to be the mother of the abandoned child.

Collocation

turn away 不准?-进入

turn down 调低；拒绝

turn in 交还；获得

turn off 关掉

turn on 打开

turn to 转向；向... 求助

2. boom vi. grow rapidly in activity, value or importance

The economy is booming.

California boomed when gold was discovered there.

3. delicate adj. needing careful handling, especially because easily broken or damaged

We need to be careful of the delicate vase.

Teaching notes

I. 1. Give students time to predict the answers.

2. Play the video.

3. Elicit the answers from students.

4. Have students summarize the main idea of the entire video.

I. 1. Have students read the useful expressions.

2. Put students into pairs and have them talk about the picture.

3. Have some pairs role-play their conversations in front of the class.

4. Give them some comments and suggestions for improvement.

III. 1. Put students into groups of three or four. Introduce the task.

2. Go through the information in the table.

3. Give students time to do the research, find the information and complete the table.

4. Invite a representative from each group to report to the class. Encourage groups to prepare PowerPoint presentations of their findings.

5. When a group is making a report, ask other groups to take notes.

6. After all the groups finish their reports, have students check their notes in their groups, or summarize other groups '

findings.

I. Watch Part 1. Decide whether the following statements are true (T) or false (F).

___ F __This part focuses on the types of the Rocky Mountain locust.

___ F __Locusts exist on all continents.

___ T __An unbelievable event happened in 1875 when weather conditions helped to create the "perfect swa rm. ”

___ T __The "perfect swarm caused extensive damage to the vegetation.

___F___The worst storm disappeared in a few hours.

___T___Locusts could hurt people physically and emotionally.

II. Watch again. Fill in the blanks with the missing information.

This part is mainly about the history and the present situation of the Rocky Mountain locust in (1) North America. In the mid-

1800s, thousands of pioneers journeyed across the . in search of (2) free land and (3) new opportunities. They settled on the frontier of the western states, and began to (4) farm the land intensively. Then, in 1875, there was a disaster caused by the a

huge swarm of locusts. (5) Trillions of insects came together over the state of Texas, and flew quickly across the frontier in (6) a huge destructive cloud that was nearly (7) 3,000 kilometers long. The locusts (8) eventually went as far west as the Rocky

Mountains, destroying everything (9) wherever they went. However, today people can't see any locusts in North America because the Rocky Mountain locust simply (10) vanished.

III. Oral work. Work with your partner. Make an interview between a news reporter and a person who witnessed the perfect

swarm. Ask and answer questions about the disaster. The witness should try to explain and act out what he or she had seen, heard and felt.

Useful expressions

What did you see What did you hear

What did you do Why did you run back to your home

How did you feel How about the other people Locusts

coming down from the sky like hail; looking with hungry eyes; turning this way and that; blocking the sun; bringing dark ness; claws diggi ng into their skin and hung upon their clothi ng …

People

screaming into their homes; hearing sharp cracks as the insects came underfoot …

I. Watch part 2. Choose the true statements about the Rocky Mountain locust.

_____ The Rocky Mountain locust died as a result of a tremendous series of earthquakes, tidal waves and forest fires.

___ V The extinction of locusts remains a mystery in the history.

_____ The reason why the Rocky Mountain locust became extinct is not something Dr. Jeff Lockwood is interested in.

_____ Locusts suffered a long and slow death.

_____ Locusts suffered a sudden demise.

___ V_T_he whole body of a locust is found in the ice.

II. Watch again. Answer the following questions in five words or less.

1.

How many years has Dr. Jeff Lockwood spent on the mysterious phenomenon Over a decade.

2. What did the extinction of the Rocky Mountain locust change

American history.

3. In what condition are the few locust specimens

They are often in bad condition.

4. How would locusts die in the Rocky Mountain

They would freeze to death.

5. Where did Dr. Lockwood find the locust specimen

On one of the steeper parts of the mountain.

III. Oral work. Explain to your partner the reasons why Dr. Jeff Lockwood leads his team to the Rocky Mountain. Use the information you've learned in this part and the expressions below.

Useful expressions

very few locust specimens exist and they are in bad condition

a body of evidence of the victim in its dying moments

what the life of the victim looked like when it was flourishing

a major set of clues is locked up in the ice

extracting DNA samples from specimens

specifying exactly what caused the extinction of the insects

I. Watch part 3. Put the following statements in the correct order.

A. Extract DNA samples.

B. Ensure the locusts they have are the right species.

C. Take the locusts back to the laboratory to examine them more closely.

D. Find signs that the locusts didn't die of old age.

E. Realize the importance of looking at the species at the time of its weakest link.

F. Conclude there must be some other force leading to the sudden death.

(C ) -( B )-( A )-( D )-( F )-(E)

II. Watch again. Fill in the blanks in the table with the missing words.

How did they know they had the Rocky Mountain locust

How do the locusts generally behave

What do the locusts look like when they are annoyed

What happens to their wings and legs when they are angry

What fact does the DNA test indicate

It was an exact match.

They're generally shy and remain alone.

They change completely into some kind of destructive monster.

They grow longer.

They didn't decline over a long period of time.

III. Listen and repeat. You are going to hear five sentences selected from the video. Repeat each sentence after it is spoken twice. Then write the sentences.

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