The Mystery of the Flashing FirefliesDuring summer nights fireflies flash in the
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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. |
| A．The Cool Light of Fireflies | B．Watching Fireflies Flash |
| C．Understanding the Patterns | D．Learning from Fireflies |
| A．shines brighter | B．does not fade | C．lasts longer | D．is not hot |
| A．Paragraph 2 | B．Paragraph 3 | C．Paragraph 4 | D．Paragraph 5 |
| A．tell why fireflies light up | B．give facts about fireflies |
| C．show how fireflies help doctors | D．compare a firefly to a light bulb |
答案
解析
举一反三
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 answ
er 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 |
| A．the earth , the oceans and the sky | B．man-made things |
| C．plants and animals | D．ocean water |
| A．more nutrition and oxygen | B．more signals |
| C．more salt | D．water |
| A．in wet regions | B．in dry regions |
| C．at very high or very low temperatures | D．when salty water falls in |
| A．they cannot explain many things | B．they know nothing about the world |
| C．they know little about the world | D．they want to be scientists |
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 |
| 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. |
| A．confused | B．absorbed |
| C．dangerous | D．excited |
| 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. |
| 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 |
B
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 |
| 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 |
| 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 re lax themselves p roperly |
| D．are more unlikely to run into mental problems |
| A．appeared troubled | B．became energetic |
| C．felt dissatisfied | D．were much depressed |
| 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 |
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 Engli
sh 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. |
| A．an English teacher | B．an English boy |
| C．an English textbook | D．a character in an English textbook |
| 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. |
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 colder | B．be getting warmer |
| C．remain the same in the past ten years | D．have good effects on the world’s population |
| 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. |
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. |
| A．Droughts and Floods. | B．Meteorologists |
| C．The Changing Climate | D．Solar Heat |
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