单选题The Polynesians who colonized Hawaii sometime between A.D. 500 and A.D. 1,000 found use for many indigenous plants.

单选题Now I don't want to {{U}}intrude{{/U}} because John's house is full of visitors.

单选题The earliest form of artificial lighting was fire, which also provided warm and protection. A. hot B. sunshine C. warmth D. safe

单选题Teenagers in the 1950s, who had to ______ an increasingly atomized family life and domestic and international tensions, scorned the sterile version of American life.

单选题The big retailers are starting to think small, too. Sainsbury's and Tesco have launched convenience-store chains, called Local and Express, respectively—that have fast become ______ in British towns.

单选题Careful testing is {{U}}necessary{{/U}} before any more experiments can continue with the exploring submarine.

单选题His ______ behavior made everyone nervous. He was always rushing to open doors and perform other small tasks, apologizing unnecessarily for any inconvenience that he might have caused. A．oblivious B．observant C．obsequious D．obsolescent

单选题There was no enmity between us, so we were able to reach an agreement on the sale of the property.

单选题Some of these online services are free, while others ______ a charge.

单选题Our holiday {{U}}is doomed{{/U}} to failure without you.

单选题An educational theorist, Paul Woodring probably summed up James's significance to education most succinctly. A. concisely B. broadly C. precautiously D. conclusively

单选题The environmental balance among ecological communities is exceedingly complex.

单选题The food was divided ______ according to the age and size of the child. A. equally B. individually C. sufficiently D. proportionally

单选题All the staff members of the department made zealous efforts to clean up the hall for the Christmas party. A. enthusiastic B. concerted C. gigantic D. dedicated

单选题In addition to cultural differences, overseas students have to overcome linguistic ______ as soon as possible.

单选题That MGM Grand Youth Center is open to children 3-12 years old ______ what hotel they are staying in. A. regardless in B. regardless of C. regardless on D. regardless from

单选题Since the shipment consists of seasonable goods, it is important that it is______as soon as possible. A. deleted B. demanded C. delivered D. detached

单选题Timmer is known as a touch manager who demands ______ results． A．credible B．undeniable C．dynamic D．tangible

单选题Most people would be impressed by the high quality of medicine available to most Americans. There is a lot of specialization , a great deal of attention to the individual, a vast amount of advanced technical equipment, and intense effort not to make mistakes because of the financial risk which doctors and hospitals must face in the courts if they handle things badly. But the Americans are in a mess . The problem is the way in which health care is organized and financed. Contrary to public belief, it is not just a free competition system. To the private system has been joined a large public system, because private care was simply not looking after the less fortunate and the elderly. But even with this huge public part of the system, which this year will eat up 84. 5 billion dollars—more than 10 percent of the U.S. budget—large numbers of Americans are left out . These include about half the 11 million unemployed and those who fail to meet the strict limits on income fixed by a government trying to make savings where it can. The basic problem, however, is that there is no central control over the health system. There is no limit to what doctors and hospitals charge for their services, other than what the public is able to pay. The number of doctors has shot up and prices have climbed. When faced with toothache, a sick child, or a heart attack, all the unfortunate person concerned can do is pay up. Two-thirds of the population are covered by medical insurance. Doctors charge as much as they want knowing that the insurance company will pay the bill. The medical profession has as a result become America"s new big businessmen. The average income of doctors has now reached $ 100,000 a year. With such vast incomes the talk in the doctor"s surgery is as likely to be about the doctor"s latest financial deal, as about whether the minor operation he is recommending at, several thousand dollars is entirely necessary. The rising cost of medicine in the U. S.A. is among the most worrying problem facing the country. In 1981 the country"s health cost climbed 15.9 percent—about twice as fast as prices in general.

单选题On turning round the corner we saw the road ______ steeply. A. falling B. decreasing C. descending D. lowering