单选题Her father was a quiet man with graceful manners.

单选题Let's arrange the provisional meeting for next Wednesday, even though we may have to change it.A. tentativeB. practicalC. localD. commercial

单选题The word “thrift ”in paragraph 1 could be best replaced by

单选题How can we reduce the risk of cancer?

单选题It took us a long time to mend the house.

单选题In most places, the edges of the continents slope gradually before making a sharp drop to the ocean floor.A. randomB. suddenC. dangerousD. brief

单选题 Valuing Childhood The value of childhood is easily blurred (模糊) in today's world. Consider some recent developments, the child-murders in the Jonesboro, Ark, schoolyard shooting case were convicted and sentenced. Two boys, 7 and 8, were charged in the murder of an 11-year-old girl in Chicago. Children who commit horrible crimes appear to act of their own will. Yet, as legal proceedings in Jonesboro showed, the one boy who was "to address the court couldn't begin to explain his acts, though he tried to apologize. There may have been a motive youthful jealousy and resentment. But a deeper question remains. Why did these boys and others in similar trouble apparently lack any inner, moral restraint (束缚)? That question echoes for the accused in Chicago, young as they are. They wanted the girl's bicycle, a selfish impulse (冲动) common enough among kids. Redemption (拯救) is a practical necessity. How can value be restored to young lives distorted (扭曲) by acts of violence? The boys in Jonesboro and in Chicago will be confined in institutions for a relatively short time. Despite horror at what was done children are not—cannot be dealt with as adults, not if a people wants to consider itself civilized. That's why politicians' cries for adult treatment of youthful criminals ultimately miss the point. But the moral void (真空) that invites violence has many sources. Family instability (不稳定) contributes. So does economic stress. That void, however, can be filled. The work starts with parents, who have to ask themselves whether they're doing enough to give their children a firm sense of right and wrong. Are they really monitoring their activities and their developing processes of thought? Schools, too, have a role in building character. So do youth organizations. So do law enforcement agencies, which can do more to inform the young about laws, their meaning. And their observance(遵守).

单选题The agenda will be choosen through an ongoing process of consultations with officials of governments and international organizations.A. continuingB. easygoingC. outgoingD. stopping

单选题Dating from around A. D. 1000, the largest mound surviving from the Mississippian culture was one hundred feet high and had a base of nearly fifteen acres.

单选题Stop {{U}}clambering{{/U}} over my sister's furniture.

单选题IQ-gene In the angry debate over how much of IQ comes from the genes that children inherit from parents and how much comes from experiences, one little fact gets overlooked: no one has identified any genes (other than those that cause retardation) that affect intelligence. So researchers led by Robert Plomin of London's Institute of Psychiatry decided to look for some. They figured that if you want to find a "smart gene," you should look in smart kids. They therefore examined the DNA of students like those who are so bright that they take college entrance exams four years early — and still score at Princeton-caliber levels. The scientists found what they sought. "We have, " says Plomin, "the first specific gene ever associated with general intelligence. " Plomin's colleagues drew blood from two groups of 51 children each. all 6 to 15 years old and living in six counties around Cleveland. In one group, the average IQ is 103. All the children are white. Isolating the blood cells, the researchers then examined each child's chromosome 6. Of the 37 landmarks on chromosome 6 that the researchers looked for, one jumped out: a form of gene called IGF2R occurred in twice as many children in the high-IQ group as in the average group — 32 percent versus 16 percent. The study, in the May issue of the journal Psychological Science, concludes that it is this form of the IGF2R gene that contributes to intelligence. Some geneticists see major problems with the IQ-gene study. One is the possibility that Plomin's group fell for "chopsticks fallacy". Geneticists might think they've found a gene for chopsticks flexibility, but all they've really found is a gene more common in Asians than, say, Africans. Similarly, Plomin's IQ gene might simply be one that is more common in groups that emphasize academic achievement. "What is the gene that they've found reflects ethnicity?" asks geneticist Andrew Feinberg of Johns Hopkins University. "That alone might explain the link to intelligence, since IQ tests are known for being culturally sensitive and affected by a child's environment. " And Neil Risch of Standford University points out that if you look for 37 genes on a chromosome, as the researchers did, and find that one is more common in smarter kids, that might reflect pure chance rather than a causal link between the gene and intelligence. Warns Feinberg: "I would take these findings with a whole box of salt. /

单选题Once Daily Pill Could Simplify HIV Treatment Bristol-Myers Squibb and Gilead Sciences have combined many HIV drugs into a single pill. Sometimes the best medicine is more than one kind of medicine. Malaria, tuberculosis and HIV/AIDS, 1 , are all treated with combinations of drugs. But that can mean a lot of pill to take. It would be 2 drug companies combined all the medicines into a single pill, taken just once a day. Now, two companies say they have done that for people just 3 treatment for HIV, the virus that causes AIDS. The companies are Bristol-Myers Squibb and Gilead Science. They have 4 a single pill that combines three drugs currently on the market. Bristol-Myers Squibb sells one of them 5 the name of Sustiva. Gilead combined the 6 , Emtriva and Viread, into a single pill in two thousand four. Combining drugs involves more than 7 issues. It also involves issues of competition 8 the drugs are made by different companies. The new once-daily pill is the result of 9 is described as the first joint venture agreement of its kind in the treatment of HIV. In January the New England Journal of Medicine published a study of the new pill. Researcher compared its 10 to that of the widely used combination of Sustiva and Combivir. Combivir 11 two drugs, AZT and 3TC. The researchers say that after one year of treatment, the new pill sup- pressed HIV levels in more patients and with fewer 12 effects. Gilead paid for the study. Professor Joel Gallant at the Johns Hopkins School of Medicine in Baltimore, Maryland, led the research. He is a paid adviser to Gilead and Bristol-Meyers Squibb as well as the maker of Combivir, Glaxo Smith Kline. Glaxo Smith Kline reacted 13 the findings by saying that a single study is of limited value. It says the effectiveness of Combivir has been shown in each of more than fifty studies. The price of the new once-daily pill has not been announced. But Gilead and Bristol-Myers Squibb say they will provide it at reduced cost to developing countries. They plan in the next few months to ask the United States Food and Drug Administration to approve the new pill. There are limits to who could take it 14 the different drugs it contains. For example, 15 women are told not to take Sustiva because of the risk of birth disorders. Experts say more than forty million people around the world are living with HIV.

单选题The teacher posted the schedule of classes. A. timetable B. plan C. list D. index

单选题He was rather vague about the reasons why he never finished school.

单选题Can we resume the meeting?

单选题When once you have caught the disease, you are {{U}}immune{{/U}} from it for the rest of your life.

单选题A result of nuclear explosion,fallout is the descent of minute particles of radioactive materiaI through the atmosphere.

单选题France has kept intimate links with its former African territories. A．friendly B．private C．strong D．secret

单选题Gambling is lawful in Nevada.

单选题 Avalanche and Its Safety An avalanche is a sudden and rapid flow of snow, often mixed with air and water, down a mountainside. Avalanches are {{U}} {{U}} 1 {{/U}} {{/U}}the biggest dangers in the mountains for both life and property. All avalanches are caused by an over-burden of material, typically snowpack, that is too massive and unstable for the slope {{U}} {{U}} 2 {{/U}} {{/U}}supports it. Determining the critical load, the amount of over-burden which is {{U}} {{U}} 3 {{/U}} {{/U}}to cause an avalanche, {{U}} {{U}} 4 {{/U}} {{/U}}a complex task involving the evaluation of a number of factors. Terrain slopes flatter than 25 degrees or steeper than 60 degrees typically have a low {{U}} {{U}} 5 {{/U}} {{/U}}of avalanche. Snow does not {{U}} {{U}} 6 {{/U}} {{/U}}significantly on steep slopes; also, snow does not {{U}} {{U}} 7 {{/U}} {{/U}}easily on flat slopes. Human-triggered avalanches have the greatest incidence when the snow's angle of rest is {{U}} {{U}} 8 {{/U}} {{/U}}35 degrees and 45 degrees; the critical angle, the angle at which the human incidence of avalanches is greatest, is 38 degrees. The rule of thumb is. A slope that is {{U}} {{U}} 9 {{/U}} {{/U}}enough to hold snow but steep enough to ski has the potential to generate an avalanche, regardless of the angle. Additionally, avalanche risk increases with {{U}} {{U}} 10 {{/U}} {{/U}}that is, the more a slope is disturbed by skiers, the more likely it is that an avalanche will occur. Due to the complexity of the subject, winter travelling in the backcountry is never 100% safe. Good avalanche safety is a continuous {{U}} {{U}} 11 {{/U}} {{/U}}, including route selection and examination of the snowpack, weather {{U}} {{U}} 12 {{/U}} {{/U}}, and human factors. Several well-known good habits can also {{U}} {{U}} 13 {{/U}} {{/U}}the risk. If local authorities issue avalanche risk reports, they should be considered and all warnings should be paid {{U}} {{U}} 14 {{/U}} {{/U}}to. Never follow in the tracks of others without your own evaluations; snow conditions are almost certain to have changed since they were made. Observe the terrain and note obvious avalanche paths where plants are {{U}} {{U}} 15 {{/U}} {{/U}}or damaged. Avoid traveling below others who might trigger an avalanche.