题目
题型：不详难度：来源：
But fishing out the largest fish from a population has an unwanted effect: Over time, fewer adult fish get really big. If only the smaller fish reproduce（繁殖）, then future generations become smaller. This is an example of evolution（进化） in action.
One scientist, Dr David Conover has spent the last decade studying the effects of the “keep the big ones” rule and if they can be reversed（颠倒）.
To set up his experiment, Conover and his team caught hundreds of silverside fish and divided them into six groups. For two groups, Conover followed the “keep the large ones” rule and took out the biggest fish. For two other groups, he removed only the small fish.
For the last two groups, he removed fish at random (随意的).
After five years, he measured the fish in each group. In the two groups where the largest fish were regularly removed, the average fish size was smaller than the average size in the other groups. Here was evolution in action: If only small fish survive to reproduce, then future generations of fish will also tend to be small.
For the second five years of his experiment, Conover changed the rules and took fish randomly from each group. At the end of the experiment, he found that the fish that were in the “keep the large ones” group for the first five years had started to get larger again, although he calculated it would take at least 12 years for the fish in that group to return to their original size.
In other words, it takes less time to shrink(变小) than it does to recover.
小题1: The underlined word “it” (Line 2) refers to “ ”
| A．the activity | B．the fish |
| C．the rule | D．the fisherman |
| A．It helps to protect fish numbers. |
| B．It helps to protect fish size. |
| C．It is the custom in most countries. |
| D．They will be punished if they don’t. |
| A．The “keep the big ones” rule made no difference to fish size. |
| B．The “keep the big ones” rule made fish smaller on average. |
| C．The “keep the big ones” rule made the fish bigger on average. |
| D．The “keep the big ones” rule affected all fish populations in the same way. |
| A．To encourage people to fish more carefully. |
| B．To urge governments to change the rules of fishing. |
| C．To describe the results of a scientific experiment. |
| D．To introduce the rules of fishing to readers. |
答案
小题1:C
小题2:A
小题3:B
小题4:C
解析
试题分析：这篇短文主要通过实验的方式验证是否可以颠覆“抓大放小”的钓鱼潜规则，以利于鱼的数量的稳定。
小题1:细节理解题。根据短文every fisherman knows the rule: Keep the big ones, throw the smaller ones back.的描述可知，这里指的是“抓大放小”的规则。故选C。
小题2:细节理解题。根据短文第一段 If you keep the smaller ones, they won’t be able to reproduce, and the fish population is in danger的描述可知，“抓大放小”的规则有利于保护雨的数量。故选A。
小题3:细节理解题。根据短文第六段 In the two groups where the largest fish were regularly removed, the average fish size was smaller than the average size in the other groups的描述可知，“抓大放小”的规则让鱼总体变小。故选B。
小题4:主旨大意题。文章主要通过实验的方式验证是否可以颠覆“抓大放小”的钓鱼潜规则，描述科学实验的结果。故选C。
核心考点
试题【Fishing is a popular activity and every fisherman knows the rule: Keep the big o】；主要考察你对科普环保类等知识点的理解。[详细]
举一反三
Mary’s story is not unusual in Britain. According to the latest government figures, pupil absences are rising, despite schools taking a hard line on truancy (逃学)．
Philippa James, a PhD researcher at Cardiff University’s school of social sciences, thinks she knows why: “The more schools improve methods of detection（检查）, the more children work out better methods of deception.” Teenagers told her it was now harder to skip a single lesson, so they’d miss whole days to avoid being caught.
For several years, James has researched student truancy of 60 teenagers, aged 13 and 14, including Mary, to see how the teenagers truant, for how long, and why.
Through online conversations and face-to-face interviews, she discovered that most truancy was “a response to factors within the school”. Truants are not necessarily less advanced or less intelligent. They complained of teachers who failed to engage them, and of “boring” lessons. “Many truants really enjoy school and believe in education, but drop out when aspects of it were ineffective.” James says.
The views of students like Adam, who believes that skipping lessons has little impact on his schooling, were common. “I only take-off for a lesson, or a couple of days. It doesn’t affect my education,” he told James.
James’ study concludes that schools need to address the question of why pupils want to leave in the first place. “Pupils need help from the start.” she says. “It’s a two-way process – schools must be responsive. We need to look at the reasons for truancy rather than the number, so that instead of walking away from school, students have the skills and chances to talk through problems and make a change.”
小题1:What is one of the reasons for school truancy according to James’ study?
| A．Truants are fallen behind in their studies. |
| B．Truants have no interest in school subjects. |
| C．Truants have more interesting things to do. |
| D．Truants are not satisfied with the teachers. |
| A．experiencing a problem with | B．having a strict attitude towards |
| C．finding it difficult to solve | D．having little success with |
| A．school education is not efficient and needs improvement |
| B．it’s a popular belief that occasional truancy won"t cause much harm |
| C．school truancy is becoming more serious and needs more concern |
| D．even good students may sometimes need a break from school |
| A．Schools should solve the problem of teachers. |
| B．Schools should be more active in helping beginner truants. |
| C．Schools should have a better control of hidden truants. |
| D．Schools should find out who truant and how they it. |
The introduction of school uniforms has helped to 小题6:___ school violence. Much of school violence is linked to the clothes which different youth gangs wear. In schools with youth gangs, the number of fights 小题7:___ by 40 percent after uniforms were introduced. Uniforms also 小题8:____ a message that students are at school to study, not to play. They create school 小题9:_____. These things help to reform problem students and improve their 小题10:____ at school.
It is always more important to know how to study by oneself than to memorize some facts or a formula（公式）. It is actually quite easy to learn a certain fact in history or a formula in math. But it is very difficult to use a formula in working out a math problem.
Great scientists didn’t get everything from school. For example, Edison didn’t even finish primary school. But they were all so successful. They invented so many things . The reason for their success was that they knew how to study. They read books that were not taught at school. They would ask many questions as they read. They did thousands of experiments. They worked hard all their lives, wasting not a single moment. Above all, they knew how to use their brain.
小题1: According to the passage, the most important thing a teacher should do is _______.
| A．to teach his students everything he knows |
| B．to teach the students how to think |
| C．to know everything they want to know |
| D．to teach the students how to work out a math problem |
| A．a certain formula | B．a certain fact |
| C．some facts | D．the way to solve it |
| A．Great scientists read a lot of books and asked many questions while reading. |
| B．Great scientists did thousands of experiments. |
| C．Great scientists always worked hard and never wasted time. |
| D．Great scientists got everything from school. |
| A．how to memorize some facts or a formula（公式） |
| B．who the great scientists are |
| C．How to study |
| D．why Edison didn’t finish primary school |
The sun is probably the world’s first “clock”, except in the far north, where the Eskimos(爱斯基摩人) live. There, it’s dark most of the winter, and light most of the summer. But in most of the world, people have used the sun as a clock. Even today, if you don’t have a clock, you can still know that when the sun shines, it’s day and when it’s dark, it’s night. The sun can also tell you if it’s morning, noon, or afternoon.
Some people live near the sea from the tides. In the daytime, for about six hours, water rises higher and higher on the beach. And then it goes down and down for about six hours. The same thing happens again at night. There are two high tides and two low tides every 24 hours. Seamen on the ship learn how to tell time by looking at the moon and the stars. The whole sky is their clock.
In some places in the world the wind comes up at about the same time every day or changes direction or stops blowing. In these places the wind can be the clock.
A sand clock is an even better clock. If you had fine dry sand in a glass shaped like the one in the picture, you would have what is called an hourglass. The sand in the hourglass goes from the top part to the bottom in exactly one hour. When the hourglass is turned over, the sand will take another hour to go back again
小题1: From the passage we can know there are _______ways to tell time besides the clock and watch.
| A．3 | B．4 | C．5 | D．7 |
| A．they know very little about the sun |
| B．the sun there never goes down in winter |
| C．it’s too cold for them to go out to watch the sun |
| D．it has long dark winters and long light summers |
| A．洋流 | B．潮汐 | C．海啸 | D．波浪 |
| A．News | B．Science | C．Advertisement | D．Sports |
| A．Different Ways to Tell Time | B．How the Clock Was Invented |
| C．The Development of the Clock | D．A Useful Machine to Tell Time |
小题1: According to the passage, we know that the first human-sheep looks like________.
| A．a sheep | B．a goat |
| C．a cat | D．an elephant |
| A．sheep will be cleverer and stronger in the future |
| B．sheep are as important as human in the future |
| C．sheep will take the place of humans in the future |
| D．animal organs may be used in human bodies |
| A．humans will change into animals |
| B．There will be fewer and fewer animals in the future |
| C．the organs may bring animal viruses into human bodies |
| D．many animals will be dead after they give their organs to humans |
| A．created a new stem cell | B．created a new creature |
| C．created a new organ | D．created a new food |
| A．The world’s first human-sheep is 15% percent human and 85% sheep |
| B．The world’s first human-sheep has many organs that are part-human |
| C．Zanjani created the world’s first human-sheep to make the sheep grows faster |
| D．The world’s first human-sheep is a sheep with the body of a sheep and half-human organs. |
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