单选题To have a better understanding of a poem, one should A. discuss It with others. B. analyze it by oneself. C. copy It down in a notebook. D practise reading it aloud.
单选题Contact your doctor if the cough
persists
.
单选题It is no use debating the relative merits of this policy. A. making B. taking C. discussing D. expecting
单选题The local Uauthorities/U will take measures to deal with noise pollution in the area.
单选题{{B}}第三篇{{/B}}
{{B}}Clone Farm{{/B}} Factory farming could soon enter a new
era of mass production. Companies in the US are developing the technology needed
to "clone" chickens on a massive scale. Once a chicken with desirable traits has
been bred or genetically engineered, tens of thousands of eggs, which will hatch
into identical copies, could roll off the production lines every hour. Billions
of clones could be produced each year to supply chicken farms with birds that
all grow at the same rate, have the same amount of meat and taste the
same. This, at least, is the vision of the US's National
Institute of Science and Technology, which has given Origen Therapeutics of
Burlingame, California, and Embrex of North Carolina $4.7 million to help fund
research. The prospect has alarmed animal welfare groups, who fear it could
increase the suffering of farm birds. That's unlikely to put off
the poultry industry, however, which wants disease-resistant birds that grow
faster on less food. "Producers would like the same meat quantity but to use
reduced inputs to get there," says Mike Fitzgerald of Origen. To meet this
demand, Origen aims to "create an animal that is effectively a clone", he says.
Normal cloning doesn't work in birds because eggs can't be removed and
implanted. Instead, the company is trying to bulk-grow embryonic stem cells
taken from fertilized eggs as soon as they're laid, "The trick is to culture the
cells without them starting to distinguish, so they remain pluripotent," says
Fitzgerald. Using a long-established technique, these donor
cells will then be injected into the embryo of a freshly laid, fertilized
recipient egg, forming a chick that is. a "chimera". Strictly speaking a chimera
isn't a clone, because it contains cells from both donor and recipient. But
Fitzgerald says it will be enough if, say, 95 percent of a chicken's body
develops from donor cells. "In the poultry world, it doesn't matter if it's not
100 percent," he says. Another challenge for Origen is to scale
up production. To do this, it has teamed up with Embrex, which produces machines
that can inject vaccines into up to 50,000 eggs an hour. Embrex is now trying to
modify the machines to locate the embryo and inject the cells into precisely the
right spot without killing it. In future, Origen imagines
freezing stem cells from different strains of chicken. If orders come in for a
particular strain, millions of eggs could be produced in months or even weeks.
At present, maintaining all the varieties the market might call for is too
expensive for breeders, and it takes years to breed enough chickens to produce
the billions of eggs that farmers need.
单选题In a laughter clinic, doctors
单选题Japan has a long trading tradition.
单选题This is not typical of English, but is a (feature) of the Chinese language.
单选题Many experts now believe that even if all space littering were to stop completely, the number of stray objects would continue to increase for centuries. The reason : debris is now so dense that objects will continue to crash into each other, creating even more objects, expanding the rubbish cloud geometrically. "We've been saying for years that these things are going to happen," says Nicholas Johnson, head of NASA's Orbital Debris Program Office. "Until they happen, it's hard to get people's interest. " What seems to best describe Nicholas Johnson's attitude towards what has happened?A. He is happy that people are starting to pay attention to the problem.B. He is critical that people have not paid enough attention to the problem.C. He is objective when commenting on the problem of cosmic junk.D. He is supportive to what people have done to deal with the problem.
单选题When you get angry, which of the followings should you do for the sake of health?
单选题The most successful magazines’ covers _____________.
单选题We"ll give every teacher
space
to develop.
单选题The conclusion can be
deduced
from the premises.
单选题Driven to Distraction Joe Coyne slides into the driver's seat, starts up the car and heads to town. The empty stretch of interstate gives way to urban congestion, and Coyne hits the brakes as a pedestrian suddenly crosses the street in front of him. But even if he hadn't stopped in time, the woman would have been safe. She isn't real. Neither is the town. And Coyne isn't really driving. Coyne is demonstrating a computerized driving simulator that is helping researchers at Old Dominion University (ODU) examine how in-vehicle guidance systems affect the person behind the wheel. The researchers want to know if such systems, which give audible or written directions, are too distracting — or whether any distractions are offset by the benefits drivers get from having help finding their way in unfamiliar locations. "We're looking at the performance and mental workload of drivers," said Caryl Baldwin, the assistant psychology professor leading the research, which involves measuring drivers' reaction time and brain activity as they respond to auditory and visual Cues. The researchers just completed a study of the mental workload involved in driving through different kinds of environments and heavy vs. light traffic. Preliminary results show that as people "get into more challenging driving situations, they don't have any extra mental energy to respond to something else in the environment," Baldwin said. But the tradeoffs could be worth it, she said. The next step is to test different ways of giving drivers navigational information and how those methods change the drivers' mental workload. "Is it best if they see a picture...that shows their position, a map kind of display?" Baldwin said. "Is it best if they hear it?" Navigational systems now on the market give point-by-point directions that follow a prescribed route. "They're very unforgiving," Baldwin said. "If you miss a turn, they can almost seem to get angry." That style of directions also can be frustrating for people who prefer more general instructions. But such broad directions can confuse drivers who prefer route directions, Baldwin said. Perhaps manufacturers should allow drivers to choose the style of directions they want, or modify systems to present some information in a way that makes sense10 for people who prefer the survey style, she said. Interestingly, other research has shown that about 60 percent of men prefer the survey style, while 60 percent women prefer the route style, Baldwin said. This explains the classic little thing of why men don't like to stop and ask for directions and women do, Baldwin added.
单选题According to politicians, when children commit crimes, they should be treated in the same way as
单选题He holds an important position in the company;
nevertheless
, I don"t quite trust him.
单选题Regular visits from a social worker can be of
immense
value to old people living alone.
单选题{{B}}第三篇{{/B}}
{{B}}Common-cold Sense{{/B}} You can't beat it, but you don't
have to join it. Maybe it got the name "common cold" because it's more common in
winter. The fact is, though, being cold doesn't have anything to do with getting
one. Colds are caused by the spread of rhinoviruses, and, at least so far,
medical science is better at telling you how to avoid getting one than how to
get rid of one. Children are the most common way cold viruses
are spread to adults, because they have more colds than adults—an average of
about eight per year. Why do kids seem so much more easily to get colds than
their parents? Simple. They haven't had the opportunity to become immune to many
cold viruses. There are more than 150 different cold viruses,
and you never have the same one twice. Being infected by one makes you immune to
it--but only it. Colds ale usually spread by direct contact, not
sneezing or coughing. From another person's hand to your hand and then to your
nose or eyes is the most common route. The highest concentration of cold viruses
anywhere is found under the thumbnails of a boy, although the viruses can
survive for hours on skin or other smooth surfaces. Hygiene is
your best defense. Wash your hands frequently, preferably with a disinfectant
soap, especially when children in your household have colds. But
even careful hygiene won't ward off every cold. So, what works when a coughing,
sneezing, runny nose strikes? The old prescription of two
aspirins, lots of water, and bed rest is a good place to start. But you'll also
find some of the folk remedies.., worth Wing. Hot mixtures of sugar (or honey),
lemon, and water have real benefits. rhinovirus n. 鼻病毒
immune adj. 免疫的,有免疫力 disinfectant n. 消毒剂,杀菌剂
prescription n. 诀窍;处方,药方 sneeze vi. 打喷嚏
thumbnail n.拇指
单选题Television Television—that most pervasive (普遍深入的) and persuasive of modern technologies marked by rapid change and growth—is moving into a new era, an era of extraordinary sophistication and versatility, which promises to reshape our lives and our world. It is an electronic revolution of sorts, made possible by the marriage of television and computer technologies. The word "television", derived from its Greek (tele: distant) and Latin (vision: sight) roots, can literally be interpreted as sight from a distance. Very simply put, it works in this way: through a sophisticated system of electronics, television provides the capability of converting an image (focused on a special photo conductive plate within a camera) into electronic impulses, which can be sent through a wire or cable. These impulses, when fed into a receiver (television set), can then be electronically reconstituted into that same image. Television is more than just an electronics system, however. It is a means of expression, as well as a vehicle for communication, and as such becomes a powerful tool for reaching other human beings. The field of television can be divided into two categories determined by its means of transmission. First, there is broadcast television, which reaches the masses through broad-based air-waves transmission of television signals. Second, there is non-broadcast television, which provides for the needs of individuals or specific interest groups through controlled transmission techniques. Traditionally, television has been a medium of the masses. We are most familiar with broadcast television because it has been with us for about thirty-seven years in a form similar to what exists today. During those years, it has been controlled, for the most part, by the broadcast networks, ABC, NBC, and CBS, who have been the major purveyors of news, information, and entertainment. These giants of broadcasting have actually shaped not only television but our perception of it as well. We have come to look upon the picture tube as a source of entertainment, placing our role in this dynamic medium as the passive viewer.
单选题We are going to have the TV
fixed
.
