The Mystery of the Flashing FirefliesDuring summer nights fireflies flash in the

The Mystery of the Flashing FirefliesDuring summer nights fireflies flash in the

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The Mystery of the Flashing Fireflies
During summer nights fireflies flash in the darkness. They look like bright spots of light dancing on the breeze. Catching them in a jar for a few minutes can be fun. Fireflies are not really flies, though. They are winged beetles. Scientists are using these special beetles to learn more about our world.
The reason a firefly flashed its light is to find a mate. There are around two thousand species, or kinds, of fireflies. Fireflies mate only with their own species. Each kind of firefly has its own flash pattern. It is important that fireflies recognize this pattern. That way they can find bugs of their own kind. The male firefly flies around in the sky while the female firefly stays close to the ground.
For many years, how a firefly flashes its light was a mystery. Scientists now know that a firefly’s light is a cold light. It gives off all of its power as light. It does not produce heat. A normal light bulb gives off only ten percent of its power as light. The rest of the power is wasted as heat. That is why a light bulb that has been on for a while is very hot. The firefly’s light does not feel hot like a light bulb.
Scientists have also learned that fireflies have a small built-in lantern. This special lantern is located inside a firefly’s body. To create light, a gas flows through tiny tubes. This causes the firefly to light up. A firefly can also turn its light on and off quickly. This puzzled scientists. They learned that short bursts of this gas make the firefly glow. When the gas fades, the light goes out. This process happens very quickly.
Scientists know that what they learn from fireflies will be important. Medical studies using fireflies are helping scientists fight illnesses in human beings. They have made new medicines from the chemicals used by fireflies to make light. Fireflies have also helped with new discoveries. New flashlights and flares have been made based on fireflies. These new flashlights and flares produce a cold light like a firefly. This way all the power makes the light shine. This little bug may be a pleasure to watch, but it is also an important part of our lives.
小题1:Why did the author most likely include Paragraph 4?
A.To explain how fireflies make light.B.To describe different kinds of fireflies.
C.To show how much power fireflies use.D.To describe why fireflies make light.
小题2:Which of these is the best choice for a heading for Paragraph 5?
A.The Cool Light of FirefliesB.Watching Fireflies Flash
C.Understanding the PatternsD.Learning from Fireflies
小题3:According to the passage, a firefly’s light is different from a light bulb’s light because the firefly’s light _______.
A.shines brighterB.does not fadeC.lasts longerD.is not hot
小题4:A reader asks this question about the passage: “ How many different kinds of fireflies are there?” Which paragraph from the passage answers the question?
A.Paragraph 2B.Paragraph 3C.Paragraph 4D.Paragraph 5
小题5:The author most likely wrote this passage in order to __.
A.tell why fireflies light upB.give facts about fireflies
C.show how fireflies help doctorsD.compare a firefly to a light bulb

答案
小题1:A小题1:D小题1:D小题1:A小题1:B
解析

举一反三
It is natural that children are curious (好奇的) about the world around them. For example, they want to know how their hearts beat. They want to know why the ocean water tastes salty.
  As children grow up, they become curious about different kinds of things. When they are babies, they are interested in the parts of their bodies and in the smiles of their mothers. They become interested in the physical world around them: the plants, the animals, the sky. Later, they become interested in the things that people have made: wheels, bicycles, cars. And when they are adults, their curiosity continues. Sometimes this curiosity leads to a career (生涯、职业) in science.
  Scientists spend their lives trying to find out about the world. Those who work with the earth sciences study the earth, the oceans, and the skies. Other scientists who study living things work with the biological sciences. A third group of scientists study the physical sciences, e. g. physics, chemistry .
  These scientists have already discovered a lot about our world. For example, they tell us why your heart beats fast when you run. They say that when you are quiet, your heart normally beats sixty-five or seventy-five times a minute. Your heart is a pump (泵) that pumps blood to all parts of the body. The blood carries oxygen and nutrition. When you run, your muscles work very hard and use the nutrition that the blood carries to them. The muscles need oxygen, too . So your brain sends a signal to the heart. The signal means that the muscles need more nutrition and oxygen. Then the heart beats fast and sends blood quickly to the muscles. It may beat 90 to 140 times a minute.
  Of course, scientists cannot answer all of our questions. If we ask, “Why does the ocean water taste salty” scientists will say that the salt comes from rocks. When a rock gets very hot or very cold, it cracks. Rain falls into cracks. The rain then carries the salt into the earth and into the rivers. The rivers carry the salt into the ocean. But then we ask , “What happens to the salt in the ocean? The ocean does not get saltier every year.” Scientists are not sure about the answer to this question.
  We know a lot about our world, but there are still many answers that we do not have, and we are curious.
小题1:According to the passage, which of the following statements is true?
A.People are curious in the same way.
B.People in different countries are interested in different things.
C.Men and women are curious about different things.
D.People of different ages are interested in different things
小题2:Scientists who work with the biological sciences study____.
A.the earth , the oceans and the sky B.man-made things
C.plants and animals D.ocean water
小题3:When you run, your muscles need ____.
A.more nutrition and oxygenB.more signals
C.more saltD.water
小题4:A rock cracks _____.
A.in wet regions B.in dry regions
C.at very high or very low temperaturesD.when salty water falls in
小题5:People are always curious because ____.
A.they cannot explain many thingsB.they know nothing about the world
C.they know little about the world D.they want to be scientists

题型:不详难度:| 查看答案
More parents are looking to cellphones to help keep their children safe.  But mom and dad should be careful: Kids who talk on a cellphone may be more likely to step into traffic. Children should learn to end phone conversations before they prepare to step into traffic.
While research shows that older kids and more experienced users also don’t navigate(穿行于) streets as well while on a cellphone, younger children tends to find the small tools more distracting(令人分心的).
“Kids of this age are just learning to cross the street on their own, ”says David-Schwebel, a co-author of the study. “They’re beginners. ”
Kids don’t need to be stopped from chatting on the phone when outside,
however. Instead, parents simply should instruct them to finish their conversations before crossing the street.        
“I don’t think this means parents should take phones away from their kids, ”says Schwebel. “I encourage families to get cellphones for their children.  They’re more helpful than harmful,  if they’re used in a safe way. ”
Other distractions, such as conversations with friends, listening to music,  and text messaging, may also cause problems for children in this age group.  The researchers expect to study the effect of those types of distractions in the future.
Experts in child safety approved the cellphone study. “If you’re talking on a cellphone,  you’re not paying much attention to the environment around you, ” says Susan Baker, a professor.
Brooke Carlson, a 44-year-old mom, has noticed how riveted her 9-year-old son is when he’s talking on the cellphone. Although she’d never thought of the dangers of crossing traffic while on the phone, Carlson says, “Now that I know about it, it makes total sense. ”She plans to have a chat with her child about cellphones and street safety.
For younger kids, parents might consider purchasing a phone with a plan that only allows the child to call up his or her parents. That way the cellphone can be used for emergencies, but not for chatting with friends for hours.
小题1:In Schwebel’s opinion, _____ .
A.kids are still too young to walk on the street alone
B.kids don’t know how to use cellphones appropriately
C.kids have little experience in crossing the street alone
D.kids are not experienced cellphone users
小题2: Which of the following is Schwebel in favor of?
A.Children shouldn’t be allowed to have a cellphone.
B.Children should be forbidden to chat on the phone when outside.
C.Cellphones do more harm to children than other distractions.
D.Parents should teach kids about cellphones and street safety.
小题3: The underlined word “riveted” may mean“_____”.
A.confusedB.absorbed
C.dangerousD.excited
小题4: According to the passage, what does Mrs Carlson know?
A.There are dangers of crossing streets while on the phone.
B.Her 9-year-old son is not interested in talking on the phone.
C.Cellphones are more helpful than harmful to children.
D.Kids don’t pay attention to the environment when talking on the phone.
小题5: The purpose of writing this passage is to _____.
A.advise parents not to buy cellphones for children
B.introduce a phone that only allows kids to call up parents
C.expect kids not to talk on cellphones while on the street
D.expect people to use cellphones less in daily life

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阅读下列短文, 从每题所给的选项(A、B、C和D)中,选出最佳选项,并在答题卷上将该项涂黑。

 Two experts did some experiments on two groups of people — one who tended to sleep less than the
people around them and the other group more.
According to their report that the “short sleepers” had been more or less average in their sleep needs until the men were in their teens. But at about age 15 or so, the men automatically began to cut down their nightly sleep time because of pressures from school, work, and other activities. These men tended to view their nightly periods of unconsciousness as bothersome interruptions in their daily routines.
   In general, these “short sleepers” appeared with ambition, active, energetic, cheerful, and conformist (不动摇) in their opinions, and very sure about their career choices. They often held several jobs at once, or even worked full time while going to school. And many of them had a strong urge to appear “acceptable” or “outstanding” to their friends and associates.
  When asked to recall their dreams, the “short sleepers” did poorly. More than this, they seemed to prefer not remembering them. In similar fashion, their usual way of dealing with psychological problems was to deny that the problem existed, and then to keep busy in the hope that the trouble would go away.
  The experts also stated that those “long sleepers” were quite different indeed. They reported that those men had been lengthy sleeps since childhood. They seemed to enjoy their sleep, protected it, and were a bit concerned when they were occasionally deprived of their desired 9 hours of nightly bed rest. They tended to recall their dreams much better than the “short sleepers did.
  Many of the “long sleepers” were shy, anxious, introverted (内向), inhibited (压抑), passive, mildly depressed, and unsure of themselves (particularly in social situations). Several openly express it that being asleep was a good escape from their daily problems.
All in all, proper time of sleeping should be admired, not too long, neither too short.
小题1:According to the report, ______.
A.many “short sleepers” need less sleep just by nature
B.many “short sleepers” are obliged to reduce sleep time by work
C.long sleepers sleep a longer period of time during the day
D.many “long sleepers” formed sleeping habit during childhood
小题2: Many “short sleepers” are likely to hold the view that ______.
A.sleep is a very efficient escape from the reality
B.sleep is just an item which should be denied by them
C.sleep might be a disturbing thing for their daily business
D.sleep is the best way to deal with psychological troubles
小题3: It is stated in the forth paragraph that “short sleepers” ______.
A.are ideally energetic under the pressures of life
B.often ignore the ill effect of not enough sleep
C.do not know how to relax themselves properly
D.are more unlikely to run into mental problems
小题4:Which of the following is nearest to the meaning of “… were a bit concerned” in the fifth Para?
A.appeared troubled B.became energetic
C.felt dissatisfiedD.were much depressed
小题5:Which of the following is NOT correct according to the passage?
A.If one sleeps improperly, his performance suffers and his memory is weakened
B.The sleep patterns of short sleepers are the same as those shown by “long sleepers”
C.Long and short sleepers differ in their attitudes towards sleep
D.Short sleepers may have been better off if they have more rest

题型:不详难度:| 查看答案
“Who is Gogo?” Almost every pupil in Hong Kong, Japan, Taiwan and Thailand will tell you: “Gogo is from outer space and is teaching children to speak and read English.”
Gogo has visited Hong Kong, Taiwan, Japan, Thailand and Korea. Now he is in China’s mainland—“Gogo has Adventure with English” has been published by Addison Wesley Longman China Ltd (AWL).
The six level English course, full of exciting stories, educates and delights children at the same time. Gogo learns English from his friends, Tony and Jenny. The children will learn along with Gogo, enjoying all the fun he produces. Gogo has a warm place in every young learner’s heart wherever he goes.
A presentation (介绍) about Gogo was given by Beijing AWL Information Centre last November. All the pupils in Huijia School attended the presentation. A foreign teacher at Huijia later said, “The children were attracted by Gogo after only a 45-minute presentation. They remember a song taught by Gogo seven weeks later. Parents often ask me how they can help their children learn English and now there’s a programme I can direct them to.”
Clive Sawkins, Paul Price-Smiths and Gregg Schroeder worked closely at AWL to make sure that Gogo will become an easily recognized symbol (标志) of learning English wherever English is studied. “Gogo is our baby,” said Gregg. “It is very easy to get children going with Gogo.”
小题1: What is the passage mainly about?
A.Gogo visits Asian countries.B.Gogo receives high praise.
C.Children love to learn with Gogo.D.AWL introduces Gogo.
小题2: It can be learned from the passage that Gogo is       .
A.an English teacherB.an English boy
C.an English textbookD.a character in an English textbook
小题3: In what way is Gogo a great help to young learners?
A.He teaches them English through songs.
B.He teaches them English through adventure stories.
C.He helps them to remember English words.
D.He makes English lessons full of fun.

题型:不详难度:| 查看答案

There is a definite possibility that the climate of the world may be changing. Some scientists imagine that this could even mean the beginning of another ice age. The effects of such a change in climate on the human population of the world would be startling(惊人的).
Recent research suggests that the general warming trend of the past hundred years or so may be coming to an end. During the past ten years, meteorologists tell us the average temperature of the Earth has dropped about one degree Fahrenheit. This does not seem like much, but it could have effects on wind and rain patterns which influence the overall weather picture. If these patterns change a lot, it could mean that certain regions of the world may continue to have long droughts while others will possibly suffer from widespread flooding.
What regulates(调节)the climate is not exactly known. Meteorologists believe that clouds may be an important factor in regulating the amount of solar heat held by the Earth, which in turn determines the temperature of the planet. Another possibility is that man’s industrial and agricultural methods may be affecting the natural weather patterns. However, the weather is not understood well enough for scientists to say for certain what is happening to the climate and what side effects this will actually have on the world’s population.
小题1:According to the passage, the climate of the world seems to    .
A.be getting colderB.be getting warmer
C.remain the same in the past ten yearsD.have good effects on the world’s population
小题2:Which of the following is TRUE according to the passage?
A.Man’s activities have no effect on the climate.
B.Another ice age will come soon.
C.People don’t care about the changing climate.
D.Scientists are not yet sure about the reason for the changing climate.
小题3:A meteorologist is a person who        .
reads weather forecasts on radio or television 
B. thinks there will be another ice age
C. studies and knows about the weather       
D. believes there will be widespread flooding
小题4: Which of the following may be the factor(s) that affect(s) the natural weather patterns?
A.Clouds.B.The amount of heat the Earth receives.
C.Man’s industrial and agricultural methods.D.All of the above.
小题5:The best title for the passage would be         .
A.Droughts and Floods.B.Meteorologists
C.The Changing ClimateD.Solar Heat

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