单选题What are feelings for? Most nonscientists will find this a strange question. Feelings just are. They justify themselves. Emotions give meaning and depth to life. They need serve no other purpose in order to exist. On the other hand, many evolutionary biologists, in contrast to animal behaviorists, acknowledge some emotions primarily for their survival function. For both animals and humans, fear motivates the avoidance of danger, love is necessary to care for young, and anger prepares one to hold ground. But the fact that a behavior functions to serve survival need not mean that that is why it is done. Other scientists have attributed the same behavior to conditioning, to learned responses. Certainly reflexes and fixed action patterns can occur without feeling or conscious thought. A gull chick peeks at a red spot above it. The parent has a red spot on its bill(喙); the chick peeks the parent's bill. The gull parent feeds its chick when pecked on the bill. The baby gets fed. The interaction need have no emotional content. Many evolutionary biologists believe thatA. emotions do not exist.B. emotions contribute to survival.C. emotions don't give meaning and depth to life.D. only humans are capable of emotions.

单选题Which of the following is NOT true of working class Americans?

单选题The union representative put across her argument very effectively. A．explained B．invented C．considered D．accepted

单选题The police took fingerprints and identified the body.

单选题A lot of people could fall ill after drinking contaminated water. A．boiled B．polluted C．mixed D．sweetened

单选题When did British gentlemen begin to wear ties regularly?

单选题They have been living under the most appalling conditions for two years.A. dreadfulB. badC. unpleasantD. poor

单选题You don't need to carry large amounts of cash; actually all financial Ubusiness/U will be conducted by computers.

单选题College Sports in the US College sports in the United States are a huge deal. Almost all major American universities have football, baseball, basketball and hockey programs, and devote millions of dollars each year to sports. Most of them earn millions (51) as well, in television revenues, sponsorships. They also benefit (52) from the added publicity they get via their teams. Big-name universities (54) each other in the most popular sports. Football games at Michigan regularly draw crowds of over 90,000. Basketball’s national collegiate championship game is a TV (54) on a par with(与……相同或相似)any other sporting event in the United States, (55) perhaps the Super Bowl itself. At any given time during fall or winter one can (56) one’s TV set and see the top athletic programs—from schools like Michigan, UCLA, Duke and Stanford— (57) in front of packed houses and national TV audiences. The athletes themselves are recruited and provided with scholarships. College coaches identify (58) teenagers and then go into high schools to (59) the country’s best players to attend their universities. There are strict rules about (60) coaches can recruit—no recruiting calls after 9 p. m., only one official visit to a campus — but they are often bent and sometimes (61) . Top college football programs offer scholarships to 20 or 30 players each year, and those student-athletes, when they arrive (62) campus, receive free housing, tuition, meals, books, etc. In return, the players (63) the program in their sports. Football players at top colleges (64) two hours a day, four days a week from January to April. In summer, it’s back to strength and agility training four days a week until mid-August, when camp (65) and preparation for the opening of the September-to-December season begins. During the season, practices last two or three hours a day from Tuesday to Friday. Saturday is game day. Mondays are an officially mandated day of rest.

单选题Canada will {{U}}prohibit{{/U}} smoking in all offices later this year.

单选题According to the passage, which of the following is increasingly dangerous to sea creatures?

单选题Usually, in an attack of influenza, the patient"s limbs ache .

单选题Almost everyone at the meeting has different views .

单选题Problems of the Elderly Gerontologists (老年人问题学者) study how old people are treated within a society and how the elderly deal with the inevitable problems of aging, particularly those involving health and income. Health problems include normal losses in hearing, eyesight, and memory, and the increased possibility of chronic(慢性的)diseases. These losses are gradual and proceed at different rates for each individual. In general, the health of old people today is better than that of earlier generation-a condition that is likely to improve still further as more people receive better medical care throught their lives. Because most old people are no longer in the labor force, a steady source of income is necessary. Systems of pensions and benefits are characteristic of industrial societies. One example is Social Security in the U. S. , which is now increased automatically as the cost of living rises, thus reducing somewhat the effect of inflation. Although the income of retired people is about half that of working people, most manage to remain financially independent. Income needs and health are what people consider most when they decide whether to re-tire or not. Putting an end to the limit on the retirement age is not expected to cause many workers to stay on the job if they can afford to retire. The need to relieve strains on the Social Security System, however, has led to legislation that gradually raises the age at which people can get full benefits. This might force them to work longer in the future. Elderly people themselves often display high spirits, satisfaction with life, and feelings of self-worth. The important factors are health and income. The task of modern societies is to ensure that the aged have their basic needs met and that they can continue to function in the community.

单选题Obtaining Drinking Water from Air Humidity Not a plant to be seen, the desert ground is too dry. But the air contains water, and research scientists have found a (51) of obtaining drinking water from air humidity. The system is based completely on renewable energy and is therefore autonomous. Cracks permeate the dried-out desert ground and the landscape bears testimony to the lack of water. But even here, where there are no lakes, rivers or groundwater, considerable quantities of water are stored in the air. In the Negev desert in Israel, for example; annual average relative air humidity is 64 percent-in every cubic meter of air there aye 11.5 milliliters of water. German research scientists have found a way of converting this air humidity autonomously into drinkable water. "The process we have developed is based exclusively on renewable energy sources (52) thermal solar collectors and photovoltaic ceils, (53) makes this method completely energy-autonomous. It (54) will function in regions where there is no electrical infrastructure." says Siegfried Egner, head of the research team. The principle of the (55) is as follows: hygroscopic brine-saline solution which absorbs moisture runs down a tower-shaped unit and absorbs water from the air. It is then sucked (56) a tank a few meters off the ground in which a vacuum prevails. Energy from solar collector (57) up the brine, which is diluted by the water it has (58) . Because of the vacuum, the boiling point of the liquid is lower than it would be under (59) . atmospheric pressure. This effect is known from the mountains: as the atmospheric pressure there is lower than in the valley, water boils at temperatures distinctly below 100℃. The evaporated, non-saline water is condensed and runs down through a completely filled tube in a controlled manner. The gravity of this water column (60) produces the vacuum and so a vacuum pump is not needed. The reconcentrated brine (61) down the tower surface again to absorb moisture from the air. "The concept is suitable for various water (62) . Single-person units and plants supplying water to entire hotels are conceivable, "says Egner. Prototypes have been built for (63) system components-air moisture absorption and vacuum evaporation-and the research scientists have already (64) their interplay on a laboratory scale. In a further (65) the researchers intend to develop a demonstration facility.

单选题Loud noises can be irritating .

单选题The truth is that he has just been fired. A. situation B. condition C. error D. fact

单选题Why is it that small children are so Uenergetic/U?

单选题Schmidt-Morand’s favorite animal is cat.

单选题Earth's Inner Core Scientists have long struggled to understand what lies at the planet's center. Direct observation of its center is impossible, so researchers must (1) to other evidence. In 1889, a German scientist detected a severe earthquake in Japan. Geophysicists concluded that shock waves (2) jolts (晃动) from one side of Earth through the center to the other side. Then in 1936, Danish geophysicist Inge Lehmann studied the waves' (3) to determine that within Earth's core of molten (溶化了的) iron lies a solid inner core—but (4) that core was made of eluded (难倒) her. Other geophysicists quickly determined that Lehmann's inner core was composed mostly (5) iron. Since then, Lehmann's discovery has (6) conventional Earth science. But now scientists are challenging traditional theory with new and radical (7) . For example, Earth's center could actually contain an "inner core within the inner core. " claim Ishii and colleague Adam Dziewonski. Analyzing hundreds of thousands of earthquake wave (8) , they maintain that the inner core has at its heart a tiny, even more solid sphere (球体). This sphere "may be the oldest fossil (9) from the formation of Earth," says Dziewonski. Dziewonski and Ishii speculate that shortly (10) Earth formed around 4. 8 billion years ago, a giant asteroid (小行星) smashed into the young planet and nearly melted it. But Earth's center didn't quite melt; it (11) mass as the planet cooled. The core within a core may be the kernel (核心) that endured. "Its presence could change our basic ideas about the (12) of the planet," Dziewonski says. Dziewonski's idea is tame (温和的) compared to the (13) theories of independent geophysicist J. Marvin Herndon. Earth's inner core is made not of iron, he claims, but a (14) of nickel and silicon. Herndon has a truly revolutionary notion. Within the nickel silicide (硅化物) inner core is also an "inner" inner core—an 8km-wide ball of the element uranium. Uranium is radioactive. Herndon thinks the uranium releases heat energy as its atoms (15) fission-split and crash into one another in a chain reaction. In other words, we may live on top of a gigantic, "natural" nuclear power plant.