All across California, honeybees are flying away from their hives(蜂箱) and dying. Empty hives are causing a lot of worry about some important food crops.
Bees give us a lot more than delicious honey. They are pollinators（授粉者）—they enable plants to produce the fruits and nuts we enjoy by carrying pollen from one plant or flower to the next. The wind pollinates oats, corn, and wheat, but many other plants (like apple and cherry trees and melon vines) depend on insects, bats, and birds. In the U.S., millions and millions of bees kept by human beekeepers fly around doing a lot of this important work for food crops. “Bees are worth protecting because their work adds so much to our diet,” says Dr. Jeff Pettis of the Bee Research Laboratory.
California’s almond (杏仁) crop alone depends on about half the bees in the country. But now the almond crop and many others could be in trouble with so many bees dying.
Researchers at government and university labs all over the country are trying to figure out why so many bees are dying. However, bees are hard to study. Most die away from the hive, so researchers don’t have dead bodies to examine. And when researchers return to a hive after two weeks, about half the bees they studied on their first visit will be dead, replaced by new ones in the natural life cycle of bees. “It isn’t like studying a large animal like a cow that doesn’t move around much and is easy to find out in the cow field,” says Pettis.
Researchers have some ideas about what could be affecting bee health. They could be sick from poisons widely used to kill insects, or they might not be getting enough good food to stay strong. Also, tiny insects called mites feed on bees. “A virus or bacteria could also be doing the killing.” explains Pettis.
小題1:What is Paragraph 2 mainly about?
A．The wind helps pollinate.
B．Bees are important in food crops.
C．Bees give us a lot of delicious honey.
D．Cherry trees are pollinated by bees.
小題2:Bees are hard to study because ____________.
A．they move around too much
B．new bees soon replace all the bees studied by researchers
C．they are too tiny
D．they never return to hives
小題3:What could cause so many bees to die?
A．Poisons to kill birds.B．Eating too much.
C．Large insects.D．Some virus.
小題4:What can we learn from the article?
A．A large number of bees have died in the hive.
B．Without bees, some foods would disappear from our diet.
C．Only researchers in California want to know what kills bees.
D．Large animals are easier to study than tiny insects.

小題1:B
小題2:A
小題3:D
小題4:B

試題分析:蜜蜂是人類的好朋友，它們不僅給我們提供美味的蜂蜜，也幫助植物授粉，而且其中加利福尼亞的杏仁作物只能靠蜜蜂授粉才可以結(jié)果。所以當(dāng)?shù)孛鄯涞拇罅克劳鲆鹆巳藗兊膿?dān)憂，也促使研究人員努力去找到其中的原因。
小題1:B推理判斷題。文章第二段介紹了蜜蜂除了給人們提供蜂蜜以外，還可以幫助植物授粉，由此判斷B選項(xiàng)正確。
小題2:A 細(xì)節(jié)理解題。根據(jù)文章第四段Pettis說的話“It isn’t like studying a large animal like a cow that doesn’t move around much and is easy to find out in the cow field,”可知蜜蜂難以觀察的原因是它們不會(huì)呆在固定的地方，所以A選項(xiàng)正確。
小題3:D細(xì)節(jié)理解題。根據(jù)文章末段“A virus or bacteria could also be doing the killing.”可以判斷D選項(xiàng)正確。
小題4:B推理判斷題。根據(jù)文章第三段可知某些植物必須依靠蜜蜂授粉，所以如果沒有蜜蜂這些植物將不會(huì)結(jié)果實(shí)，由此判斷B選項(xiàng)正確。
練習(xí)冊(cè)系列答案
相關(guān)習(xí)題

科目：高中英語 來源：不詳 題型：閱讀理解

The weather predictions for Asia in 2050 read like a story from a doomsday movie.
Many experts and green groups fear they will come true unless there is a united global effort to hold back greenhouse gas outpouring. In the decades to come, Asia---home to more than half the world’s 63 billion people-will change from one climate extreme to another, with tired farmers battling droughts, floods, disease, food shortages and rising sea levels.
“It’s not a pretty picture,” said Steve Sawyer, climate policy adviser with Greenpeace in Amsterdam. Global warming and changes of weather patterns are already occurring and there is more than enough carbon dioxide and other greenhouse gases in the atmosphere to drive climate change for decades to come.
Already, changes are being felt in Asia but worse is likely to come, Sawyer and top climate bodies say, and could lead to mass migration and widespread human disasters. According to predictions, icebergs will melt faster, some Pacific and Indian Ocean islands will have to evacuate(疏散) or build sea defenses, storms will become more intense and insect and water-borne diseases will move into new areas as the world warms.
All this comes with rising populations and demand for food, water and other resources. Experts say environmental worsening such as deforestation and pollution will probably enlarge the results of climate change.
In what could be a sign of the future, Japan was hit by a record of 10 typhoons and tropical storms this year, while two-thirds of Bangladesh, parts of Nepal and large areas of northeastern India were flooded, affecting 50 million people, destroying livelihoods and making tens of thousands ill.
The year before, a winter cold struck and a summer heat wave killed more than 2,000 people in India.
小題1:This passage is mainly about       .
A．what kind of weather we like best
B．the weather predictions for Asia in the future and the reasons
C．how to improve our environment
D．that the world will not be suitable for us to live in
小題2:In the future the Asian farmers will have to face the following except       .
A．food shortagesB．droughtsC．warsD．floods
小題3:The underlined word “doomsday” may give us the feeling of        .
A．happinessB．sadnessC．peaceD．excitement

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

A black hole is a place in space where gravity pulls so much that even light cannot get out. The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star is dying.
Because no light can get out, people can’t see black holes. Space telescopes with special tools can help find black holes. The special tools can see how stars that are very close to black holes act differently from other ones.
Black holes can be big or small. Scientists think the smallest black holes are as small as just one atom. These black holes are very tiny but have the mass of a large mountain. Mass is the amount of matter, or “staff”, in an object.
Another kind of black hole is called “stellar”(星球黑洞). Its mass can be up to 20 times more than the mass of the sun. There may be many stellar mass black holes in Earth’s galaxy. Earth’s galaxy is called the Milky Way.
The largest black holes are called “supermassive”(超大質(zhì)量黑洞). These black holes have masses that are more than one million suns together. Scientists have found proof that every large galaxy contains a supermassive black hole at its center. The supermassive black hole at the center of the Milky Way galaxy has a mass equal to about four million suns and would fit inside a very large ball that could hold a few million Earths.
Scientists think the smallest black holes formed when the universe began. Stellar black holes are made when the center of a very big star falls in upon itself, or falls apart. When this happens, it exploded part of the star into space. Scientists think supermassive black holes were made at the same time as the galaxy they are in.
A black hole can not be seen because strong gravity pulls all of the light into the middle of the black hole. But scientists can see how the strong gravity affects the stars and gas around the black hole. Scientists can study stars to find out if they are flying around, or orbiting a black hole.
When a black hole and a star are close together, high-energy light is made. This kind of light cannot be seen with human eyes. Scientists use satellites and telescopes in space to see the high-energy light.
小題1:The gravity of a black hole may become so strong that light cannot get out when ____________.
A．the star is going to die
B．special tools are used on it
C．other stars come close to it
D．it is seen from the space telescopes
小題2:According to the passage, which of the following is NOT true?
A．A black hole can be very tiny but extremely heavy.
B．The gravity of a black hole holds all light in its center.
C．Scientists observe high-energy light through their own eyes.
D．Some small black holes came into being as early as the universe.
小題3:The underlined word “galaxy” in Paragraph 5 means __________.
A．a(chǎn) black holeB．the Milky Way
C．a(chǎn) series of starsD．a(chǎn) planet near the earth
小題4:What does the last sentence in Paragraph 5 suggest?
A．Neither the sun nor the earth is as heavy as a black hole.
B．There is a supermassive black hole at the center of the Milky Way.
C．The supermassive black hole had existed before the Milky Way was formed.
D．There is a reason why the large black holes are called “supermassive”.
小題5:The last two paragraph mainly focus on the question of _________.
A．what a black hole is
B．how black holes form
C．how big black holes are
D．how scientists know about black holes

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

Normally a student must attend a certain number of courses in order to graduate, and each course which he attends gives him a credit which he may count towards a degree. In many American universities the total work for a degree consists of thirty-six courses each lasting for one semester. A typical course consists of three classes per week for fifteen weeks; while attending a university a student will probably attend four or five courses during each semester. Normally a student would expect to take four years attending two semesters each year. It is possible to spread the period of work for the degree over a longer period. It is also possible for a student to move between one university and another during his degree course, though this is not in fact done as a regular practice.
For every course that he follows a student is given a grade, which is recorded. and the record is available for the student to show to potential employers.  All this imposes(增加)  a constant pressure and stress of work, but in spite of this some students still find time for great activity in student affairs. Elections to positions in student organizations arouse much enthusiasm. The effective work of maintaining discipline is usually performed by students who advise the academic authorities. Any student who is thought to have broken the rules, for example, by cheating has to appear before a student court. With the enormous numbers of students. the operation of the system does involve a certain amount of activity. A student who has held one of these positions of authority is much respected and it will be of benefit to him later in his career.
小題1:Normally a student would at least attend __________classes each week.
A．36B．12C．20D．15
小題2:According to the first paragraph an American student is allowed
A．to live in a different university
B．to change permanently his or her university
C．to live at home and drive to classes
D．to get two degrees from two different universities
小題3:American university students are usually under pressure of work because__________. 
A．their academic performance will affect their future careers
B．they are heavily involved in student affairs
C．they have to obey university rules
D．they want to run for positions of authority
小題4:Some students are enthusiastic for positions in student organizations probably because_________.
A．they hate the constant pressure and stress of their study
B．they will then be able to stay longer in the university
C．such positions help them get better jobs
D．such positions are usually well paid
小題5:The student organizations seem to be effective in__________.
A．dealing with the academic affairs of the university
B．ensuring that the students observe university regulations
C．evaluating students' performance by bringing them before a court
D．keeping up the students' enthusiasm for social activities

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

Play allows children to use their creativity while developing their imagination and physical, cognitive (認(rèn)知的), and emotional strength. Play is important to healthy brain development. Play allows children to create and explore a world they can master, conquering their fears while practicing adult roles. Undirected play allows children to learn how to work in groups, to share, to negotiate, and to resolve conflicts.
Ideally, much of play involves adults, but when play is controlled by adults, children acquiesce (順從) to adult rules and concerns and lose some of the benefits play offers them, particularly in developing creativity, leadership, and group skills. In contrast to passive entertainment, play builds active, healthy bodies. In fact, it has been suggested that encouraging unstructured play may be an exceptional way to increase physical activity levels in children, which is one important strategy in the resolution of the obesity problem.
Children’s development is critically influenced by appropriate, affective relationships with loving and consistent caregivers as they relate to children through play. When parents observe their children in play or join with them in child-driven play, they are given a unique opportunity to see the world from their children’s vantage point as the child navigates a world perfectly created just to fit his or her needs. The interactions that occur through play tell children that parents are fully paying attention to them and help to build enduring relationships. Parents who have the opportunity to look at their children’s world learn to communicate more effectively with their children and are given another setting to offer guidance. Less verbal children may be able to express their views, giving their parents an opportunity to gain a fuller understanding of their perspective. Quite simply, play offers parents a wonderful opportunity to engage fully with their children.
Play is essential to the academic environment. It ensures that the school setting attends to the social and emotional development of children as well as their cognitive development. It has been shown to help children adjust to the school setting and even to strengthen children’s learning willingness. Social-emotional learning is best integrated (融合) with academic learning; it is concerning if some of the forces that enhance children’s ability to learn are improved at the expense of others. Play and unscheduled time that allow for peer interactions are important components of social-emotional learning.
小題1:Compared with undirected play, play which is controlled by adults ________.
A．doesn’t benefit the children at all
B．doesn’t help develop leadership and group skills
C．makes children become more active
D．helps increase physical activity levels
小題2:The third paragraph mainly tells us that ________.
A．play offers parents a good chance to establish good relationships with children
B．children’s development is greatly influenced by relationships with parents
C．play helps children better express their views
D．play offers parents a unique opportunity to see the world from a different perspective
小題3:From the last paragraph, we know that ________.
A．play can’t help children become adapted to the school setting
B．play makes social-emotional learning and academic learning separated
C．play is beneficial to social-emotional learning as well as academic learning
D．it is necessary to strengthen children’s academic development at the expense of others
小題4:Which of the following statements is NOT true?
A．Undirected play can help children develop team spirit.
B．Play can improve children’s willingness to learn.
C．Play helps adults gain a better understanding of the children’s thoughts.
D．Adults shouldn’t be involved in children’s play.

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

You put a great deal of effort into reaching the college of your choice. It’s time to get started. But what’s next? Beginning college can be an exciting but awkward time. Follow these tips to adjust to your new life rapidly and make the most of your college experience.
● To save time and money, use the college’s bus system. Taking the bus to school is quick, easy and free in most college towns. You won’t have to locate or afford a place to park either. It’s also a good way to be environmentally aware.
● Save pennies on books by waiting until class starts. You might not even need all of the recommended books. New textbooks cost an arm and a leg. Try buying used textbooks — it’s a surefire way to save money and serves the purpose as well.
● Do never look at college life as an endless series of parties and social activities. But there is a whole lot more to college if you’re serious about graduating. Having a good college experience is all about balancing work and fun.
● Be aware that your living environment can largely affect your academic success. If the dorm doesn’t suit you, consider living at home with your family or renting your own apartment. The best location for your studies isn’t always your dorm. Find a quiet area, like the library, to do your work. Alternatively, buy some headphones that block out noise.
● Be mindful of your diet. Make healthy food choices and watch what you eat. Avoid foods that are processed or high in sugar. The “freshman 15” is real. Many college students gain at least 15 pounds during their freshmen year.
● While electives (選修課) can be helpful when figuring out your major, you shouldn’t entirely rely on them. Clubs and other organizations exist around. Get involved. Make sure, though, that you still have time to study. Having too much on your plate can hurt your grades.
小題1:Which of the following ideas can be financially wise? 
A．Driving your own car.B．Buying used books.
C．Renting an apartment.D．Attending activities.
小題2:In the text, freshmen are repeatedly warned against ______.
A．a(chǎn)cademic failuresB．physical problems
C．traffic accidentsD．social activities
小題3:The “freshman 15” tells the fact that some freshmen ______.
A．a(chǎn)ttend limited activities on campus
B．have little regular physical exercise
C．focus less on their academic work
D．take relaxed attitudes to their diets
小題4: The underlined phrase “having too much on your plate” probably refers to ______.
A．using too much money for meals
B．eating too many unhealthy foods
C．taking part in too many after-class activities
D．taking an elective that has too many students

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解



At the moment, there are two reliable ways to make electricity from sunlight. You can use a panel of solar cells to create the current directly, by liberating electrons from a semiconducting material such as silicon. Or you can concentrate the sun’s rays using mirrors, boil water with them, and employ the steam to drive a generator.
Both work. But both are expensive. Gang Chen of the Massachusetts Institute of Technology and Zhifeng Ren of Boston College therefore propose an alternative. They suggest that a phenomenon called the thermoelectric（熱電）effect might be used instead—and they have built a prototype（原型）to show that the idea is practical.
Thermoelectric devices are not new. They are used, for example, to capture waste heat from car engines. They work because certain materials generate an electrical potential difference within themselves if one part is hotter than another. That can be used to drive a current through an external circuit.
The reason thermoelectric materials have not, in the past, been applied successfully to the question of solar power is that to get a worthwhile current you have to have a significant temperature difference. (200℃ is considered a good starting point.) In a car engine, that is easy. For sunlight, however, it means concentrating the heat in some way. And if you are going to the trouble of building mirrors to do that, you might as well go down the steam-generation route, which is a much more efficient way of producing electricity. If the heat concentration could be done without all the equipment of mirrors, though, thermoelectricity’s inefficiency would be balanced by the cheapness of the equipment.
In their view, three things are needed to create a workable solar-thermoelectric device. The first is to make sure that most of the sunlight which falls on it is absorbed, rather than being reflected. The second is to choose a thermoelectric material which conducts heat badly but electricity well. The third is to be certain that the temperature gradient（梯度）which that badly conducting material creates is not wasted by poor design.
小題1:The following methods can be adopted to make electricity from sunlight EXCEPT         .
A．putting a panel of solar cells into use
B．concentrating sun’s rays with mirrors
C．creating a solar-thermoelectric device
D．building a practical solar prototype
小題2:Why was the application of thermoelectric materials a failure in the past?
A．Because it’s hard for them to build enough mirrors to make it work.
B．Because 200℃ was hard to reach at that time even in a car engine.
C．Because of the failure of having a significant temperature difference.
D．Because it was hard to focus the sun’s rays with equipment of mirrors.
小題3:Which of the following is the best title for this passage?
A．Thermoelectric Device --- the Best Method of All
B．A New Method of Making Electricity from Sunlight
C．How to Create a Workable Thermoelectric Device
D．Solar Power --- a New Energy Trend in the Future

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

Many people are aware of the beauty of a solar eclipse (日食), but are surprised to learn that lunar eclipses are often just as impressive. While total solar eclipse lasts only for a few minutes and can be seen only in a small area of a few kilometers, total lunar eclipse can last for several hours and can be seen over much of the planet. In fact, the beauty and stability of lunar eclipses make them a favorite of both amateur and professional photographers.
Lunar eclipses generally occur two or three times a year, and are possible only when the Moon is full. When we see the Moon, we are actually seeing sunlight reflected off the surface of the Moon When the Earth is positioned in between the Moon and the Sun, however, the Earth's shadow falls on the Moon, and a lunar eclipse occurs.
The type of lunar eclipse - total, partial, or penumbral (半影) - that occurs depends both on how much of the Moon passes through the Earth's shadow and through which part of the shadow it passes. A penumbral eclipse occurs when the Moon passes through the Earth's outer shadow. This type of eclipse is brief and frequently goes unobserved by all but astronomers. By contrast, total and partial eclipses occur when all or part, respectively, of the Moon passes through the umbra（本影） shadow of the Earth. These eclipses are quite easy to see and are widely observed.
Unlike solar eclipses, lunar eclipses are safe to watch. Solar radiation that occurs during an eclipse of the Sun can cause a form of burns of one's eyes known as eclipse blindness. In fact, the only way to safely view a solar eclipse is by using specially designed equipment. However, since the Moon's light is reflected sunlight, it is completely safe to watch a lunar eclipse without any special equipment, although a pair of binoculars can certainly help the viewer appreciate the beauty of this phenomenon
小題1:The underlined word "stability " most probably means_______.
A．strengthB．positionC．steadinessD．visibility
小題2:According to the passage, a partial lunar eclipse occurs________.
A．when the Moon passes between the Sun and the Earth
B．when all of the Moon passes through the Earth's umbra shadow
C．when only a part of the Moon passes through the Earth's outer shadow
D．when only a part of the Moon passes through the Earth's umbra shadow
小題3:The passage implies that penumbral eclipses are________.
A．longer-lasting than most solar eclipses
B．more common than partial or full lunar eclipse
C．the result of the shadow cast by the Moon onto the Earth
D．more difficult to observe than other types of lunar eclipse
小題4:According to the passage, it is safe to watch a lunar eclipse, unlike a solar eclipse, because ________.
A．moonlight is less strong than sunlight
B．a(chǎn) lunar eclipse is briefer than a solar eclipse
C．a(chǎn) lunar eclipse lasts much longer than a solar eclipse
D．special equipment can be employed to view a lunar eclipse

查看答案和解析>>

科目：高中英語 來源：不詳 題型：完形填空

If you do not use your arms or your legs for some time, they will become weak; and when you start using them again, they will slowly become strong again.       knows this, but nobody would think of     the fact.
Yet there are many people who        to know that the memory works in the same way. When someone says that       has a good memory, he       means that he keeps his memory in practice     exercising it very     , either consciously or unconsciously. When someone else says that his memory is     , he means that he does not give it enough      to become strong. The position is exactly the same as that of       people, one of      exercises his arms and legs by playing ball, while the other       in a chair or a car all day. If a friend of yours says that his arms are weak, we know that it is his own      , But if he tells us that he has a poor memory,      of us think that his parents are to blame, or that he is just     , and few of us realize that it is just as it was his arms or legs that were weak. Not all of us can become very strong in body or very clever in mind,       all of us can improve our strength and our memory by the same means that      .
Have you ever       that people who cannot read or write usually have      memories than those who can? Why is this? Of course, because they cannot write down something in a little notebook or something else. They have to remember names, places, songs and stories; so their memory is always being exercised.
In a word, if you want to have a good memory, do practice       things。
小題1:
A．Everybody B．SomebodyC．NobodyD．Each one
小題2:
A．provingB．questioningC．describingD．indicating
小題3:
A．wantB．haveC．seemD．need
小題4:
A．sheB．heC．itD．one
小題5:
A．a(chǎn)lwaysB．nearlyC．reallyD．a(chǎn)lmost
小題6:
A．withB．inC．to D．by
小題7:
A．oftenB．fastC．quicklyD．soon
小題8:
A．badB．uselessC．helplessD．poor
小題9:
A．timeB．chanceC．spaceD．places
小題10:
A．twoB．fourC．threeD．five
小題11:
A．themB．thatC．whomD．which
小題12:
A．liesB．sitsC．hidesD．stands
小題13:
A．businessB．interestC．storyD．fault
小題14:
A．fewB．someC．manyD．several
小題15:
A．unfortunateB．unhappyC．unthinkableD．miserable
小題16:
A．becauseB．butC．forD．since
小題17:
A．studyB．restC．playD．work
小題18:
A．noticedB．thoughtC．believedD．realized
小題19:
A．strangerB．poorerC．worseD．better
小題20:
A．rememberB．remembering.C．to rememberD．remembered

查看答案和解析>>

同步練習(xí)冊(cè)答案