单选题A typical peripheral device has ______ which the processor uses to select the devices internal registers. A．data B．a control C．a signal D．an address

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单选题This crime fiction was ______ very popular but nobody reads it today.

单选题I have really got angry with John because______I suggest, he always disagrees.

单选题______ he gave that we should take more exercise in our spare time!A. what a good adviceB. How a good adviceC. What good adviceD. How good advice

单选题{{B}}Passage 5{{/B}} Anthropologists, psychologists and others have begun seeking the roots of ambition in family, culture, gender, genes and more. They have by no means thrown the curtain all the way back, but they have begun to part it. If humans are an ambitious species, it's clear we're not the only one. Many animals are known to signal their ambitious tendencies almost from birth. Even before wolf pups are weaned, they begin sorting themselves out into alphas and all the others. The alphas are quicker, more curious, greedier for space, milk, Mom--and they stay that way for life. Alpha wolves wander widely, breed annually and may live to a geriatric 10 or 11 years old. Lower-ranking wolves enjoy none of these benefits--staying close to home, breeding rarely and usually dying before they're four. Humans often report the same kind of temperamental determinism. Families are full of stories of the inexhaustible infant who grew up to be an entrepreneur, the phlegmatic child who never really showed much go. But if it's genes that run the show, what explains identical twins--precise genetic templates of each other who ought to be temperamentally identical but often exhibit profound differences in the octane of their ambition? Ongoing studies of identical twins have measured achievement motivation--lab language for ambition--in identical siblings separated at birth, and found that each twin's profile overlaps 30% to 50% of the other's. In genetic terms, that's an awful lot--"a benchmark for heritability", says geneticist Dean Hamer of the U.S. National Cancer Institute. But that still leaves a great deal that can be determined by experiences in infancy, subsequent upbringing and countless other {{B}}imponderables{{/B}}. Some of those variables may be found by studying the function of the brain. At Washington University in St. Louis, Missouri, researchers have been conducting brain imaging to investigate a trait they call persistence--the ability to stay focused on a task until it's completed just so--which they consider one of the critical engines driving ambition. The researchers recruited a sample group of students and gave each a questionnaire designed to measure persistence level. Then they presented the students with a task--identifying sets of pictures as either pleasant or unpleasant and taken either indoors or outdoors--while conducting magnetic resonance imaging of their brains. The nature of the task was unimportant, but how strongly the subjects felt about performing it well--and where in the brain that feeling was processed--could say a lot. In general, the researchers found that students who scored highest in persistence had the greatest activity in the limbic region, the area of the brain related to emotions and habits. "The correlation was .8 [or 80%]," says professor of psychiatry Robert Cloninger, one of the investigators. "That's as good as you can get." It's impossible to say whether innate differences in the brain were driving the ambitious behavior or whether learned behavior was causing the limbic to light up. But a number of researchers believe it's possible for the nonambitious to jump-start their drive, provided the right jolt comes along. "Energy level may be genetic," says psychologist Simonton, "but a lot of times it's just finding the right thing to be ambitious about." Simonton and others often cite the case of Franklin D. Roosevelt, who might not have been the same President he became--or even become president at all--had his disabling polio not taught him valuable lessons about patience and tenacity.

单选题Noun phrases, verb phrases and prepositional phrases usually form endocentric constructions.

单选题Sally wanted to go to Florida for the holiday, but her husband thought{{U}} {{/U}},saying that they would go to New York to join his parents for Christmas.

单选题Woman: I heard John and Frank had a quarrel.Man: Oh, they soon made up.Question: What does the man mean?

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单选题In the experiment we kept a watchful eye ______ the developments and recorded every detail. [A] in [B] at [C] for [D] on

单选题The pleasures which a movie offers to our eyes have been paid for with the loss of sight of a man whose name is hardly known outside the annals of science—Joseph Plateau, a Belgian professor, born in Brussels in 1801. He studied the mechanism of sight, beginning a series of most dangerous experiments at the age of 28 by staring into the sun for 25 seconds to see what the effect on his eyes would be. He was blind for nearly a month. But he went on experimenting, increasing the length of time during which he looked into the sun, knowing that in the end this would cost him his sight. At the age of 42 he was completely and incurably blind; the sun had destroyed the retina (视网膜) of his eye. But he continued to work as well as he could until he died at the age of 82. Science profited enormously from his research. He studied the so-called "inertia of the eye" (视觉暂留) which makes a picture remain on the retina for about one-sixth of a second after it has disappeared from our vision. This means that, if we see a succession of individual pictures each of which appears only for a fraction of a second, they "overlap" in our brain; and if they show Consecutive phases of movement, that movement will appear to us to be continuous.

单选题The population of the village has decreased ______ 150 to 500.

单选题The current emergency in Mexico City that has taken over our lives is nothing. I could ever have imagined for me or my children. We are living in an environmental crisis, an air-pollution emergency of unprecedented severity. What it really means is that just to breathe here is to play a dangerous game with your health. As parents, what terrorizes us most is reports that children are at higher risk because they breathe more times per minute. What more can we do to protect them and ourselves? Our pediatrician"s (儿科医师的) medical recommendation was simple: abandon the city permanently. We are foreigners and we are among the small minority that can afford to leave. We are here because of my husband"s work. We are fascinated by Mexico—its history and rich culture. We know that for us, this is a temporary danger. However, we cannot stand for much longer the fear we feel for our boys. We cannot stop them from breathing. But for millions, there is no choice. Their lives, their jobs, their futures depend on being here. Thousands of Mexicans arrive each day in this city, desperate for economic opportunities. Thousands more are born here each day. Entire families work in the streets and practically live there. It is a familiar sight: as parents hawk goods at stoplights, their children play in the grassy highway dividers, breathing exhaust fumes. I feel guilty complaining about my personal situation. We won"t be here long enough for our children to form the impression that skies are colored only gray. And yet the government cannot do what it must to end this problem. For any country, especially a developing Third World economy like Mexico, the idea of barring from the capital city enough cars, closing enough factories and spending the necessary billions on public transportation is simply not an option. So when things get bad, as in the current emergency, Mexico takes half measures—prohibiting some more cars from circulating, stopping some factories from producing—that even its own officials concede aren"t adequate. The word "emergency" implies the unusual. But when daily life itself is an emergency, the concept loses its meaning. It is human nature to try to adapt to that which we cannot change. Or to mislead ourselves into believing we can adapt.

单选题Which of the following is TRUE of teacher’s correction of his student’s writing errors? ( )

单选题Cirque du Soleil (say it: Serk du So-lay) is being accused of out-dated thinking about the dangers of AIDS. It is a modem acrobatic circus from Canada that tours in the United States and other countries. Last April, the company fired Matthew Cusick because he was HIV positive. This was after he spent four months learning his part in an act. A spokesman for the circus said Cusick was fired for safety reasons. They said he was a danger to others. He disagreed. Hundreds of people picketed a show in San Francisco. They said that firing him was not legal. Cusick says the company knew he was HIV positive when they hired him. R was not fair to let him put so much time into learning his act, and then fire him before he performed. He says he is not a danger to others. People can only get AIDS if infected blood contacts another person's blood, or open wound. The company says what their acrobats do is very, very dangerous. They perform tricks without nets. Someone might fall and get hurt. It could be bloody. They say it is too risky to let a person with HIV take part in an act. People who run the circus say it hurts to be accused of discrimination, Matthew Cusick says he feels hurt that he can't perform in the big blue and yellow tent. Dozens of artists, actors, writers and entertainers got involved in protesting the firing of Matthew Cusick, Some names you might know are: the Actors' Equity Union (45,000 members), Rosie O'Donnell, Rod McKuen, and Chad Allen, They also protested at a showing in Orange County. They said "HIV discrimination is unacceptable./