One day, “supercharged plants” may help feed people around the world. Supercharged plants are ones that grow faster than normal plant life. Scientists can speed up the growth by modifying, or changing, the structure of plants' genes. The modifications make them react quickly to changes in light. This all has to do with photosynthesis(光合作用), the process in which plants turn sunlight, carbon dioxide and water into food.
Plants grow fastest in the sun. That is when they make the most food for themselves. But their rate of growth can slow when things like clouds or trees block sunlight. But when the sun returns, it can take many minutes for growth to speed up again.
This can be a problem because it means some of our most important crop plants are not as productive as they could be. Researchers say demand for food is expected to increase up to 70 percent by the middle of the century. They also note rising temperatures on Earth's surface. That is why they are looking for ways to improve photosynthesis and make plants more productive.
Steve Long is a plant biologist at the University of Illinois. He wanted to find a way to help plants get back up to speed quickly after a period of darkness. So he and his team added genes that shortened the recovery time. It also increased the speed at which the plants grew. His modified plants grew up to 20 percent more than untreated ones.
In Long's study, his group used a form of genetic engineering called transgenics (转基因). It means taking genes from one plant, then putting them into another. Now they are experimenting soybeans, rice, cowpeas and cassavas.
1.What is the advantage of supercharged plants?
A. They can grow more quickly.
B. They can grow in severe conditions.
C. They can offer high-quality grains.
D. They can replace normal plants.
2.What can make plant growth slow down?
A. Too hot weather. B. Old farming methods.
C. Lack of sunlight. D. Too much sunlight.
3.What was Steve Long's goal in his study?
A. To find out what makes plants grow slowly.
B. To create a new plant that can grow with weak sunlight.
C. To find another way to help plants benefit each other.
D. To make plants recover quickly when the sun returns.
4.How can researchers shorten the recovery time of plants?
A. By changing their nature. B. By adding new genes to them.
C. By developing new plants. D. By supplying more sunlight.
When I was watching some children attempting to catch butterflies on a hot July afternoon, an incident in my own childhood occurred to me. When I was 15, something happened to me, which forever cured me of desiring to put any wild life in a cage.
We lived on the edge of a wood, and every evening at dusk the mockingbirds would come and rest in the tree and sing. There isn't a musical instrument made by man that can produce a more beautiful sound than the song of the mockingbird.
I decided that I would catch a young bird and keep it in a cage and that way have my own private musician.
I finally succeeded in catching one and put it in a cage. At first, in its fright at being captured, the bird fluttered about the cage, but eventually it settled down in its new home, I felt very pleased with myself and looked forward to some beautiful singing from my tiny musician.
I had left the cage out on our back porch(门廊), and on the second day of the bird's captivity my new pet's mother flew to the cage with food in her mouth . The baby bird ate everything she brought to it. I was pleased to see this. Certainly the mother knew better than I how to feed her baby.
The following morning when I went to see how my captive was doing, I discovered it on the floor of the cage, dead. I was shocked! What had happened? I had taken excellent care of my little bird, or so I thought.
Arthur Wayne, the famous ornithologist, happened to be visiting my father at the time and, hearing me crying over the death of my bird, explained what had occurred: “A mother mockingbird, finding her young in a cage, will sometimes bring it poisonous berries. She thinks it better for her young to die than to live in captivity.”
Never since then have I caught any living creature and put it in a cage. All living creatures have a right to live free.
1.Why did the writer catch a mockingbird when he was a boy?
A. He had just got a new cage.
B. He liked its beautiful feather.
C. He wanted it to sing for him.
D. He wanted a pet for a companion.
2.Why did the mocking bird die?
A. It was frightened to death.
B. It drank the poisonous water by mistake.
C. It ate the poisonous food its mother gave it.
D. It refused to eat anything.
3.What is an ornithologist likely to be?
A. A specialist in birds. B. A religious person.
C. A headmaster. D. A considerate person.
4.What is the most important lesson the author learned from the incident?
A. Be careful about the food you give to baby birds.
B. All birds put in a cage won't live long.
C. You should keep the birds from their mothers.
D. Freedom is very valuable to all creatures.
The Digital Revolution, also known as the Third Industrial Revolution, is the shift from mechanical and analogue electronic technology to digital electronics which began anywhere from the late 1950s to the late 1970s. Central to this revolution is the mass production and widespread use of digital logic circuits, and its derived technologies. These technological innovations have transformed traditional production and business techniques.
1980s
In developed nations, computers achieved ubiquity during the 1980s as they made their way into schools, homes, business, and industry. Automated teller machines, industrial robots, CGI in film and television, electronic music, bulletin board systems, and video games all fueled what became the zeitgeist of the 1980s. Millions of people purchased home computers, making household names of early personal computer manufacturers such as Apple, Commodore, and Tandy. To this day the Commodore 64 is often cited as the best selling computer of all time, having sold 17 million units (by some accounts) between 1982 and 1994.
1990s
The first public digital HDTV broadcast was of the 1990 World Cup that June; it was played in 10 theaters in Spain and Italy. However HDTV did not become a standard until the mid-2000s outside Japan.
The World Wide Web became publicly accessible in 1991, which had been available only to government and universities. In 1993 Marc Andreessen and Eric Bina introduced Mosaic, the first web browser capable of displaying inline images and the basis for later browsers such as Netscape Navigator and Internet Explorer. Stanford Federal Credit Union was the first financial institution to offer online internet banking services to all of its members in October 1994.
2000s
Cell phones became as ubiquitous as computers by the early 2000s, with movie theaters beginning to show ads telling people to silence their phones. They also became much more advanced than phones of the 1990s, most of which only took calls or at most allowed for the playing of simple games.
2010s
By 2012, over 2 billion people used the Internet, twice the number using it in 2007. Cloud computing had entered the mainstream by the early 2010s. By 2015, tablet computers and smart phones were expected to exceed personal computers in Internet usage. By 2016, half of the world's population was connected.
1.According to the passage, which one of the following statements is true?
A. The digital revolution only focuses on the mass production.
B. The World Wide Web became available to government and universities in 1991.
C. Phones of the 1990s merely made calls.
D. The number of people using the Internet in 2007 is approximately 1 billion.
2.What does the underlined word in Paragraph Two refer to?
A. Wide existence. B. Abrupt disappearance.
C. Quick movement. D. Abundant amount.
3.How does the writer develop the whole passage?
A. By presenting times. B. By making comparisons.
C. By listing data. D. By drawing conclusions.
4.What is the best title for this passage?
A. The Traditional Production B. The Digital Revolution
C. The Connected Population D. The World Wide Web
With the advance of human society, along with the development of modern science and technology, people are faced with an increasing number of pollutions. One of the severe pollutions is noise pollution. Many parents express their complaints over noise pollution, especially car alarms.
Anchor
Almost anyone who has lived in a big city can tell you how irritating it is to be awakened in the middle of the night by the wail of a car alarm. The loss of sleep can drive you crazy, but this is just one in a long list of problems that such high decibel noises can cause.
Jonathan
People in this noisy neighborhood in upper Manhattan are fed up with car alarms. They're angry enough at being jolted awake several times a week, but more than that they worry about what effect these alarms will have on their children. Already studies have shown that continuous exposure to high-decibel noise can cause an increase in heart rate and blood pressure.
Andrea
By the time my child can read, he will already have been exposed to the constant roar of the traffic, but the intense siren of a car alarm is way above the level of safety.
Michael
I have a valid concern. According to the National Institute of Occupational Safety and Health (NIOSH), exposure to noise above 85 decibels for 8 hours or more is a danger to your health. City traffic and trucks are about 90 decibels. The siren of a car alarm is about 120 decibels, about the same as a plane taking off.
The parents here are sick and tired of listening to the shrill siren of car alarms. However, it's for their children that they are most concerned. They've started a group called Parents to Silence Car Alarms. They don't think that making the owner of a car pay a fine is enough. These parents have started a campaign to have car alarms banned.
1.According to the passage, which one of the following statements is true?
A. Anchor thinks the high decibel noises only causes the loss of sleep.
B. Jonathan holds the view that exposure to decibel noises can give rise to heart disease.
C. According to NIOSH, exposure to noise above 85 for 8 hours or more threatens people's health.
D. Andrea believes the intense siren of a car alarm is acceptable.
2.According to the passage, what is the parents' attitude towards car alarms?
A. Neutral. B. Critical. C. Favorable. D. Indifferent.
3.What is the main idea of the passage?
A. People in modern society is faced with noise pollution.
B. Anyone who lives in a big city is tired of car alarms.
C. A car alarm is out of control and beyond the level of safety.
D. Parents complain about car alarms, trying to fight against them.
听下面一段独白，回答以下小题。
1.What is the speaker mainly talking about?
A. School routines. B. Travelling plans. C. Outdoor courses.
2.What place will the listeners visit?
A. A lake. B. A forest. C. A beach.
3.What will the students learn to do?
A. Make a birdhouse. B. Build a house. C. Design a backpack.
4.How many hours will the students spend on the courses?
A. 12. B. 15. C. 36.
听下面一段较长对话，回答以下小题。
1.What are the speakers going to do on Monday?
A. Take photos of the signs.
B. Interview some native speakers.
C. Have an interview with a manager.
2.What will the speakers visit on Tuesday?
A. The education department in North County.
B. The education department in San Diego.
C. The California University.
3.How did the woman contact Mr. Cooper?
A. She mailed him.
B. She e-mailed him.
C. She telephoned him.
4.Why do the speakers take the trip?
A. To do research on languages.
B. To report the lives of the natives.
C. To make a comparison among education departments.
