Honeybees are disappearing for unknown reasons around the United States. Last winter, bees disappeared from 23 percent of American beekeeping businesses. Causes of the phenomenon, however, have remained a mystery.
Now, scientists from several universities and the United States Department of Agriculture say they have a possible explanation for the bee decline(數(shù)量下降). It is a little known virus called Israeli acute--paralysis virus (IAPV) .The virus kills bees. Researchers in Israel first described it in 2004 , but until now, bee experts hadn’t paid much attention to it.
When trying to find out why the bees were disappearing, a research team at Columbia University studied bee colonies ( 群體), some with and the others without decline. The research turned up large numbers of two types of fungi (真菌) once suspected of causing the bee decline. The research results, however, showed that the fungi were almost as common in colonies without a decline as they were in colonies with a decline. The researchers concluded that the two fungi probably weren’t the cause.
Studies of the presence of IAPV, however, showed more interesting information. In those studies, done by a team at Pennsylvania State University in University Park, the virus showed up in 83 percent of samples from colonies with symptoms (癥狀). Only five percent of samples from symptomless colonies had it.
Scientists still don’t know whether IAPIV can single--handedly cause the bee decline. They believe that even if the virus is making colonies sick , it could have a partner in crime. It’s possible, for instance, that insects or chemicals in the environment weaken bees, making them more likely to catch IAPV.
Scientists are still trying to figure out how IAPV came to the United States. The United States currently allows bee products to be imported from Canada, Australia, and New Zealand. If it turns out that this trade is spreading disease, the rules might eventually change.
68. According to the passage ,IAPV is a virus that ______.
A. hasn’t attracted much attention      
B. well-known to doctors and scientist
C. was first found by Austrian researchers  
D. is dangerous to animals and human beings
69. The underlined sentence in the fifth paragraph probably means______.
A. the virus could also cause other damages
B. there must be something that is the real cause
C. IAPV is not the only cause for the bee decline
D. the virus may be caused by the polluted environment
70. From the third and fourth paragraphs, we know researchers draw their conclusions by means of _______.
A. calculating        B. comparing  C. examining     D. investigating
71. What still remains unknown to American scientists according to the passage?
A. How and why to kill IAPV.
B. How IAPV came to America.
C. Whether bee products should be imported.
D. How to change the rules of the bee products trade.
72. The best title for this passage would be _____.
A. Bee Disease     B. How to Kill IAPV 
C. A Virus—IAPV   D. Two Types of Fungi
練習(xí)冊系列答案
相關(guān)習(xí)題

科目:高中英語 來源:不詳 題型:完形填空

My parents operated a small restaurant in Seattle. It was open twenty-four hours a day, six days a week. And my first real job,when I was six years old,was小題1:the diners’ shoes. My father had done it when he was young,so he taught me小題2:to do it efficiently,telling me to    小題3:to Re-shine the shoes if the customer wasn’t小題4:.
Working in the restaurant was a cause of great小題5:because I was also working for the good of the family. But my father小題6:that I had to meet certain standards to be part of the team. I小題7:to be punctual,hard-working,and polite to the小題8:.
I was小題9:paid for the work I did at the restaurant. One day I made the mistake of advising Dad that he小題10:give me $10 a week. He said,“OK. How about you paying me for three meals a day you have here? And小題11:the times you bring in your friends for free soft drinks?” He小題12:I owed him about $40 a week.
I remember returning to Seattle after being小題13:in the US Army for about two years. I had just been promoted to Captain at that time. And full of pride,I walked into my parents’ restaurant,but the小題14:thing Dad said was,“How about your小題15:up tonight?” I couldn’t小題16:my ears! I am an officer in the Army! But it didn’t 小題17:as far as Dad was concerned,I was just 小題18:member of the team. I reached for the mop. Working for Dad has taught me the devotion to a小題19:is above all. It has nothing to do with小題20: that team is involved in a family restaurant or the US Army.
小題21:A.cleaning                            shining                 C.removing     D.keeping
小題22:A.why  what                    C.when                  D.how
小題23:A.offer refuse                   C.love                    D.learn
小題24:A.interested annoyed       C.relaxed                D.satisfied
小題25:A.fun         pride               C.trouble                D.effort
小題26:A.got it right kept it a rule C.made it clear        D.took it for granted
小題27:A.had                 tended       C.hated               D.managed
小題28:A.family       workers  C.customers          D.friends
小題29:A.never        always     C.seldom              D.ever
小題30:A.must        should    C.might                D.could
小題31:A.a(chǎn)t                    before      C.a(chǎn)round             D.for
小題32:A.worked out   found out     C.put out    D.thought out
小題33:A.a(chǎn)lone        away       C.outside            D.off
小題34:A.usual        last          C.next                D.first
小題35:A.washing      taking    C.cleaning         D.moving
小題36:A.ignore        follow   C.believe           D.understand
小題37:A.happen       care          C.go                 D.matter
小題38:A.no                    other         C.some            D.a(chǎn)nother
小題39:A.team         family    C.leader           D.restaurant
小題40:A.why         whether    C.when           D.how

查看答案和解析>>

科目:高中英語 來源:不詳 題型:閱讀理解


Beliefs form a big part of our lives. Successful people have always believed that they can be and will be successful in their lives, such as Michael Phelps. Many of us have seen Michael Phelps win 8 gold medals in a single Olympic Games. That has created a history for himself. Many people have admired his success and the first reaction in their mind will be, “ Wow, how I wish I could be like him!” Have you ever wondered what brought him success?
In fact, anyone can achieve what they have wanted to achieve. It is about beliefs. Everyone is a born winner. It is this belief that drives an individual to be successful in his  or her own field. All successful individuals have strong beliefs and it is one of the bases  for their success. If we start to believe in ourselves, the things that we can achieve will definitely give us a pleasant surprise.
Other than having a strong belief, it is the attitude that drives the individual to create their own history. The devotion towards themselves and the drive must also be present. Imagine having a strong belief in oneself and having a poor attitude towards life. Then how would that individual turn out to be? One’s attitude comprises the drive, the devotion and the desire to achieve his goals. If one has strong beliefs about the goals that he can achieve and he displays good attitudes towards them, it would be no surprise to anyone that he will be able to achieve his goals.
Start believing in yourself and you will achieve your goals and with the right positive attitude, you will definitely be able to create the miracle that you have always dreamt of.
60.Which of the following is the best summary of Paragraph2?
A. Where there is a will, there is a way.
Good begun is half done.
No pains, no gains.
God helps those who help themselves.
61.The underlined word comprises in Paragraph3 most probably means_______?
A. serve as      B. belongs to         C. consists of       D. stands for
62.It can be inferred from the passage that ______.
A. attitudes can be learned from one’s parents
B. only strong beliefs can’t ensure you a promising future
C. copying other’s behaviors is a good way to succeed
D. attitudes can only be learned through one’s success
63.What would be the best title for the passage?
A. Differences Between Beliefs and Attitudes
B. The Nature of Beliefs and Positive Attitudes
C. Relationship Between Beliefs and Attitudes
D. The Power of Beliefs and Positive Attitudes

查看答案和解析>>

科目:高中英語 來源:不詳 題型:完形填空

第二節(jié)(共5小題;每小題2分,滿分10分)
根據(jù)短文內(nèi)容,從短文后的選項中選出能填入空白處的最佳選項。選項中有兩項為多余選項。
Students will need to use all of their skills in order to understand the reading selections in Reader’s Choice.
71    These selections provide practice on employing different reading skills to get the message of the writer. They also give students practice in four basic reading skills: skimming, scanning, reading for thorough comprehension, and critical reading.
Skimming involves reading quickly through a text to get an overall idea of its contents. This kind of rapid reading is suitable when you are trying to decide if careful reading is desirable or    72  
Like skimming, scanning is also quick reading. However, in this case the search is more    concentrated.    73    When you read to find a particular date, or number you are scanning.
Reading for thorough comprehension is carefully reading in order to understand the total   meaning of the passage. At this level of comprehension the reader is able to summarize the author’s ideas    74   .
Critical reading demands that a reader makes judgments about what he or she reads. This kind of reedit requires posting and answering questions such as “    75   ”, “Do I share the author’s point of view?” and “Am I convinced by the author’s arguments and evidence?
A.Does my own experience support that of the author?
B.Reader’s Choice is one of the most popular magazines in the world.
C.but has not yet made a critical evaluation of those ideas.
D.The book contains many types of selections on a wide variety of topics.
E To scan is to read quickly in order to find out specific information.
F. Do I know about the author?
G. when there is no time to read something carefully.

查看答案和解析>>

科目:高中英語 來源:不詳 題型:閱讀理解

.
Today, air travel is far safer than driving a car on a busy motor-way. But still there is a danger that grows every year. Airliners get larger and larger. Some airplanes can carry over 300 passengers. And the air itself becomes more and more crowded. If one large airliner struck into another in midair, 600 lives could be lost.
From the moment an airliner takes off to the moment it lands, every movement is watched on radar screens. Air traffic controllers tell the pilot exactly when to turn, when to climb, and when to come down. The air traffic controllers around a busy airport like London-Heathrow may deal with 2,500 planes a day. Not all of them actually land at the airport. Any plane that flies near the airport comes under the orders of the controllers there. Even a small mistake on their part could cause a terrible accident.
Recently such a disaster almost happened. Two large jets were flying towards the airport. One was carrying 69 passengers from Toronto, the other 176 passengers from Chicago. An air traffic controller noticed on his radar screen that the two planes were too close to each other. He ordered one to turn to the right and to climb.But he made a mistake. He ordered the wrong plane to do this. So, instead of turning away from the second plane, the first plane turned towards it. Fifteen seconds later it flew directly in front of the second plane. They avoided (避免) each other by the smallest part of a second. The distance between them was less than that of a large swimming pool. This is an example of the danger that grows every year.
61. Which of the following is true according to the passage?
A. Traveling by air is as safe as by car.
B. Traveling by air is not as safe as by car.
C. Traveling by car is as dangerous as by air.
D .Traveling by car is more dangerous than by air.
62. The air traffic controllers of an airport ____.
A. control all the planes flying near the airport
B. give orders to planes leaving the airport
C. only deal with the planes that want to land there
D. are allowed to handle 250 planes a day
63. The danger of air crashes grows every year because ____.
A. airliners are getting larger and air traffic is becoming heavier
B. a pilot does not always hear a controller’s order
C. a controller is likely to make more and more mistakes
D. airports can hardly serve the growing number of airplanes
64. The example in the passage is to show that ____.
A. air traffic controllers are often careless
B. air traffic controllers should pay much attention to avoiding accidents
C. it is difficult for airplanes to avoid terrible accidents
D. two planes should not fly too close to each other

查看答案和解析>>

科目:高中英語 來源:不詳 題型:閱讀理解

.
Why is there no risk to the customer when a bank prints the customer’s name to his cheques?
When anyone opens a current account at a bank, he is lending the bank money, repayment of which he may demand at any time, either in cash or by drawing a check in favor of another person. Primarily, the bank-customer’s account is in credit or overdrawn. But, in addition to that basically simple concept, the bank and its customer owe a large number of obligations(義務(wù)) to one another. Many of these obligations can give rise to problems but a bank customer, unlike, say, a buyer of goods, cannot complain that the law is loaded against him.
The bank must obey its customer’s instructions, and not those of anyone else. When, for example, a customer first opens an account, he instructs the bank to debit(把......記入借方) his account only in respect of checks drawn by himself. He gives the bank specimens(標(biāo)本) of his signature, and there is a very firm rule that the bank has no right to pay out a customer’s money on a check on which its customer’s signature has been forged(偽造). It makes no difference that the forgery may have been a very skillful one: the bank must recognize its customer’s signature. For this reason there is no risk to the customer in the practice, adopted by banks, of printing the customer’s name on his checks. If this helps forgery, it is the bank which will lose, not the customer.
1. When you have a bank account, you ___
A.must always be in credit
B.can’t draw any money if you’re overdrawn
C.can draw money without notice
D.can’t pay money to anyone else
2. One of the obligations a bank has to a customer_____
A.is that it can’t take instructions from other people
B.is that it can avoid complications and problems
C.it must pay money to the customer even if he is seriously overdrawn
D.it must print the customer’s signature
3. The underlined part “the law is loaded against him” in the second paragraph is most likely to mean_____
A.the law is not of his interest
B.the law is unfavorable to him
C.the law is not in favor of him
D.the law is not in his honor
4. If someone forged your signature and drew money from your account___
A.the bank would always pay money to the forger
B.the bank wouldn’t lose any money
C.you wouldn’t lose any money
D.you wouldn’t lose your money

查看答案和解析>>

科目:高中英語 來源:不詳 題型:閱讀理解

.
Sometimes children do not do what their parents tell them to do. When this happens, a parent tries to help the child to do the right thing. When this does not work, the parent usually punishes the child.
There are many things that a parent can do. One thing that people have done is to spank (打屁股) the child. When a parent spanks a child, they will use their hand or a hard object to strike them on their bottom. This is meant to show the child that they have done something wrong.
One parent remembers being spanked when he was a child. His parents used a wooden spoon. When he spanked his own children with his hand, he saw that he put a red mark on his child’s leg. He never did that again.
One problem with spanking is that it teaches the child to hit someone when they do not like what the other person is doing. Another problem with spanking is that the parent is usually angry and can hit the child too hard. Sometimes parents will use spanking for everything and not try other ways to get the child to do the right thing.
Many parents are not sure of what to do instead of spanking. Some people think that their religion tells them that spanking is okay. Some think that the law lets them do it. The courts (法院) say that parents have the right to teach their children how to behave.
Other things should be tried before a parent decides to spank a child. Telling the child exactly what is wanted from them can be one thing. Giving a child more than one choice is another thing that can be tried. Getting down to the child’s level and taking a more child-friendly approach (方法) can help as well.
67. According to the passage, when children do something wrong, one thing that parents usually do to punish them is to ________.
A. strike them on the bottom
B. try to help them do the right thing
C. teach them what to do
D. take them to court
68. Which of the following is NOT the problem caused by spanking?
A. It teaches the child to hit others when they offend(使人不快) him or her.
B. The parent may get angry and hit the child too hard.
C. Sometimes parents may use spanking for everything.
D. It makes parents try other ways to make the child do right.
69. Which of the following can best describe the writer’s attitude towards spanking?
A. favorable (贊同的)   B. indifferent (不關(guān)心)
C. interested          D. unfavorable
70. From this passage, we can conclude that ________.
A. Good children always do the right thing.
B. Parents should try their best to avoid (避免) spanking their children.
C. Parents have no choice but to spank their children when they do something wrong.
D. Children can have more than one choice to avoid being spanked.

查看答案和解析>>

科目:高中英語 來源:不詳 題型:閱讀理解

.
It was Christmas, and there was a big party in the house. Guests came and went, but the party went on. Then the bell rang. Several people shouted, “come in!” A small man opened the front door and came in. Nobody knew him but the host went to meet him and took him to have a drink. The man sat there happily for an hour and drank. Then suddenly he stopped and looked at the host. “Do you know me?” he said. “Nobody asked me to this party. I don’t know you. I don’t know your wife and I don’t know any of your guests. My wife and I wanted to go out in our car, but one of your guests’ car was in front of our gate, So I came here to find him and my wife is waiting in our car for me to come back.” 
60. When the bell rang, the guests ___ .
A. were shouting                 B. were singing and dancing
C. were enjoying themselves        D. were waiting for the small man 
61. The host __ after the small man came in.
A. was glad to see him            B. asked him to have a drink
C. didn’t find him                 D. knew who he was
62. The small man went to the house ___ .
A. to find a man                   B. to have a drink
C. to have a party                  D. to see what was happening
63. Perhaps the small man’s wife got ___ because ___ .
A. hungry; he drank too much   
B. surprised; he couldn’t find the man
C. lonely; he didn’t take her to the party
D. angry; he kept her waiting for a long time

查看答案和解析>>

科目:高中英語 來源:不詳 題型:閱讀理解

.
The Festival of Cultures (August 11 – 14)
City Park
The Festival of Cultures is an annual event to celebrate the wide range of cultures found in our great state. People representing 40 cultural groups will share their traditions and customs. Here are just a few of the festival’s many activities.
Crafts (手工): See the fine art of basket weaving from Vietnam and Zimbabwe. Watch the delicate art of making paper umbrellas from Thailand and the decorative craft of paperl picado, or paper cutting, from Mexico. All craft demonstrations provide a firsthand view of how things are made. You will appreciate the process involved in making these products.
Music and Dance: Experience musical instruments that you have never heard before. Listening to the music of a sho from Japan, a bull-roarer from Australia, a sitar from India, and a chakay from Tailand. You will also be entertained by folk dances from around the world, such as the troika from Russia and the mayim from Israel. From 1:00 P.M. to 3:00 P.M. on August 14, special folk-dancing classes for children will be offered. Children ranging in age from 6 – 8 can learn the kinderpolka from Germany. Children ranging in age from 9 – 12 can learn the raspa from Mexico.
Storytelling: Listen for hours as professional storytellers charm you with interesting tales. Fables, folktales, and ballads from various countries will be told. By popular demand, Gwendolyn Washington, a famous African American storyteller, is back.
Food: Enjoy irresistible foods from other countries, such as gyros from Greece, seafood paella from Spain,
crepes from France, and tandoori chicken from India. These tasty dishes will be difficult to pass up.
Tickets August 11 - 13
Adults            $3
Ages 13 – 18       $2
Ages 6 – 12        $ 1
Ages 6 and under    Free
      
Tickets August 14
Adults            $3
Ages 13 – 18       $2
Ages 12 and under  Free
 
87. Which of the following are from Mexico?
A. The paper cutting and troika.    B. The kinderpolka and sitar.
C. The paperl picado and the raspo.      D. The mayim mayim and the gyros.
88. A family with two children at the age of 8 and 16 are going to the festival on August 12. How much money will they pay for the festival?
A. $5.     B. $6.     C. $8.     D. $9.
89. What do we know about the festival?
A. Children will have a chance to learn different folk-dancing.
B. Storyteller Gwendolyn is invited to the festival for the first time.
C. People will be offered opportunities to play musical instruments.
D. Visitors can make paper umbrellas from their first- hand experience.
90. What’s the purpose of writing this passage?
A. To advertise for the World Marketplace.
B. To introduce a wide range of cultural traditions.
C. To explain the great significance of popularizing the festival.
D. To persuade readers to attend the festival held in the City Park.

查看答案和解析>>

同步練習(xí)冊答案