Fishing is a popular activity and every fisherman knows the rule: Keep the big ones, throw the smaller ones back. The idea behind Lt is simple - the larger fish are probably older. If you keep the smaller ones, they won’t be able to reproduce, and the fish population is in danger.
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. The underlined word “it” (Line 2) refers to “ ”
| A．the activity | B．the fish |
| C．the rule | D．the fisherman |
Why do many people follow the “keep the big ones, throw the small ones back” rule?
| 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. |
What did Conover find after the first five years of his experiment?
| 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. |
What is the author’s intention in writing this article?
| 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. |
阅读下面材料 ，从每题所给的三个选项（A、B和C）中，选出最佳选项。
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This is a mystery story book. Two children called Calder and Petra try to find out who stole an expensive Vermeer painting. Look at each picture in the book carefully. There is something hidden in each one. |
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This game is good for your thumbs(拇指) and fingers. You have to press the lights when they light up. Do you think it sounds easy? Well, think again because it’s very difficult. If you miss a lot of lights, you’ll not win the game. |
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This might look like a toy, but it’s a talking Internet phone. Just connect the Verballs to your USB port on your computer and you can phone all your friends all around the world. You’ll have fun with it! |
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This is a colorful set which will help you to paint. Each color has a number and the numbers are on the picture for you to follow. Painting beautifully has never been easier. Everyone will think you are the next teenager genius. |
What can be found in the pictures in the book Chasing Vermeer?
A. The background of the story.
B. Something about the thief.
C. The value of the painting. What do the players do when playing the game GYA-II?
A. They press the lights with thumbs and fingers.
B. They call their foreign friends to play together.
C. They follow the numbers of the set colors.The writer thinks it fun to______.
A. read the book Chasing Vermeer
B. paint pictures with the colorful set
C. phone friends all over the worldWhich of the following can be used to talk on the Internet?
A. Chasing Vermeer. B. GYA-II. C. Verballs. How does the writer think of painting with the colorful set?
A. Easy. B. Wonderful. C. Difficult.
Friendship is a very important human relationship and everyone needs good friends. Good friendship has many benefits. It offers companionship, improves self-worth and promotes good health. There are times in our lives such as when we have recently moved into a new town, or changed our jobs or schools. Such changes often leaves us without a friend. Making new friends comes easy for some people. But for many of us the process is difficult and requires courage. Below are some helpful suggestions on how to make and keep friends.
Associate with others
The first step to making friends is associating with other people. You can go to public places to meet new people. Besides, you will need to make yourself known by becoming an active member of such places.
Start a conversation
Starting a conversation is the second most important step in making new friends. Do not wait to be spoken to. You can always start the conversation. Being able to make small talk is a very useful skill in relating with other people.
Do things together
Choosing friends with common interests is important in building friendship as these interests would always bring you and your friend together. Hanging out will always be a pleasant experience.
Let it grow
It is a good thing to stay in touch. However, try not to press your new friend with calls, messages or visits as this would likely wear him or her out and finally you may lose your friend. So you will need to give your friend time to react to you. The best friendships are the ones that grow naturally.
Enjoy your friendship
The best way to enjoy your friendship is to allow your friends to be themselves. Try not to find fault with your friends. Try not to change them from who they are to what you want them to be. Become the kind of friend you will want your friend to be to you.Is friendship very important for everyone?
How do you associate with others?
Why is choosing friends with common interests important?
What will you do to enjoy your friendship according to the passage?
What’s the passage mainly about?
If Tomb Sweeping Day(清明节) gives you a holiday to go outdoors, Spring break is what teenagers in the US look forward to.
Unlike our semester, which starts in late February or early March this year, . So in late March and April, most American schools, ranging from kindergartens to colleges, give students one to two weeks off school.
What do students do during the time? , but they all beat studying!
Some kids take trips with their parents, visiting a new state or even a new country. There is one place in the US that all kids dream about going on their Spring Break — Disney World in Florida. For some kids that dream will come true. .
For many, Spring break means relaxing or family reunions. They may stay home, read and watch movies, or they may go to visit friends. Others may travel to visit family members who live far away. . On a ten-day trip, for example, students may go on a tour through Spain, France, and Italy. These trips are often expensive, but they give students a great chance to see other parts of the world.
Students in the US don’t have their Spring break at the same time. . So while students from one town are on vacation, their neighbors in the next town may have classes as usual.
| A. They’ll get to meet Mickey Mouse B. Sometimes teachers lead overseas trips for groups of students C. American schools begin as early as January D. It depends on where they live E. They like to do many things |
Although most people believe that laughter is one of the nature’s great treatments for a whole range of mental and physical diseases, it is still a serious scientific subject that researchers are trying to figure out.
“Laughter above all else is a social thing,” says Baltimore neuroscientist(神经科学家), Robert Provine, who has studied laughter for many years. “All laughter groups laugh ‘ha-ha-ha’ basically the same way. Whether you speak Mandarin, French or English, everyone will understand laughter. There is a pattern generator(发生器) in our brain that produces this sound.”
Laughing is our first way of communicating. Babies laugh long before they speak. No one teaches them how to laugh. They just do. People may laugh at a prank(恶作剧) on April Fools’ Day. But surprisingly, only 10 to 15 percent of laughter is the result of someone making a joke. Laughter is mostly about social responses rather to a joke. Deaf people laugh without hearing and people on cell phones laugh without seeing, showing that laughter isn’t dependent on single sense but on social interactions.
And laughter is not just a people thing. Chimps tickle(挠痒) each other and even laugh when another chimp pretends to tickle them.
Jaak Panksepp, a Bowling Green University Psychology professor, studies rats that laugh when he tickles them. It turns out rats love to be tickled — they return again and again to the hands of researchers tickling them.
By studying rats, scientists can figure out what’s going on in the brain during laughter. Northwestern University biomedical engineering professor, Jeffrey Burgdorf has found that laughter in rats produces a chemical that acts as an antidepressant(抗抑郁药). He thinks the same thing probably happens in humans, too. This would give doctors a new chemical target to develop drugs that can fight depression.
Even so, laughter itself has not been proved to be the best medicine, experts said. Margaret Stuber, a professor at University of California, studied whether laugher helped patients. She found that distraction(分心) and mood improvement helped, but she could not find a benefit of laughter alone.
“No study has shown that laughter produces a direct health benefit,” Provine said, mainly because it’s hard to separate laughter from just feeling good. But he thinks it doesn’t really matter: “Isn’t the fact that laughter feels good when you do it enough?”The underlined word “figure out” in Paragraph 6 means “________”.
| A．deal with | B．work out |
| C．look out of | D．come up with |
According to the passage, scientists studied rats in order to find ______.
| A．how they laugh |
| B．if they like laughing |
| C．what laughter in rats produces |
| D．how rats react while being tickled |
What can we know from Robert Provine’s research?
| A．Laughter makes a person feel good. |
| B．Laughter produces a direct health benefit. |
| C．Laughter depends on all kinds of senses. |
| D．Laughter is a way of communicating. |
What is probably the best title for this passage?
| A．Why Rats Laugh |
| B．When Laughter Happens |
| C．How Laughter Works |
| D．Why Laughter Matters |
Some people say that today, reading is not as important as it was. These days we have photographs, films, radio and television. Why read a description of something when you can look at a photograph? Why read a newspaper when the latest news is brought to us every hour on radio and TV?
Photography was certainly a wonderful invention. Photographs can give a very clear idea of places and of people that we have never seen. An encyclopedia (百科全书) , for example, is always better when it has good illustrations. But we also need words to explain the photographs and drawings. A photograph of an elephant may give us a very good idea of what an elephant looks like, but it tells us nothing about the different sorts of elephants there are and where they are found, their exact size and weight, how they can be useful to man and so on.
In the same way, a good film has action, movement, color, and maybe music. These are things we do not find on the printed page. But reading a novel has certain advantages over watching even an excellent feature film. Reading a novel requires imagination. Each of us imagines a story differently.
Watching news on television can certainly be exciting. But we need newspapers as well. Some important news stories happen when there are no cameras around. More importantly, a newspaper does not just report the news. It explains why something has been happening. It also contains interesting articles on different subjects. Newspapers are an important part of our lives, if we want to understand what is going on in the places we live as well as in other parts of the world.
Reading is very important for information and pleasure. We need to be good readers to enjoy a full life as human beings. Reading is a skill and like other skills, it needs practice. The more we read, the better readers we become. And the better readers we become, the more we enjoy reading! The secret is to get the reading habit. Read at least a little every day.According to Paragraph 2, photographs can give us __________.
| A．enough information about people and places |
| B．no information about things |
| C．some information about things but not enough |
| D．the wrong information about things |
Newspapers contain __________.
| A．more information than television |
| B．less information than television |
| C．more news from other countries |
| D．less information about important events than TV |
What are the advantages of novel over a feature film?
| A．There are more interesting subjects in novels. |
| B．We do not hear any music in a novel. |
| C．Novels always explain what is happening. |
| D．Novels make us use our imagination. |
What does the author think about reading?
| A．It is a wonderful invention. |
| B．It is an important part of our lives. |
| C．It requires no practices. |
| D．It is not as important as television. |
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