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教学的科学性是指教学内容要正确地反映客观世界及其运动规律，教给学生科学知识。( )
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The wet volcanic ash that covered a Maya village in Central America in about AD 595 coated and preserved everyday objects beans, chilies, rope, gourds, even unwashed dishes -- just as they had been left, giving archaeologists a rare chance to learn about the everyday lives of the people of this pre-Columbian village. Exploration of the site, which is located in E1 Salvador and has been given the name Joya de Ceren, is now in its eighth season, and archaeologists are continuing to make new finds. The volcanic eruption that entombed Ceren more than 1,400 years ago began when lava pushed its way close enough to the surface to create a great explosion of steam and. ash that was centered just north of the village. The archaeologists have not found the remains of any human beings killed by the eruption in Ceren, suggesting that they had enough warning to flee. The eruption buried Ceren in a layer of ash 4 to 6 m (13 to 20 ft) deep over a period of a few days. One of the most striking of the conclusions drawn from the Ceren site is that the people of this ancient village lived more comfortably than average Salvadorans do today. Ceren’s architecture, crafts, and agriculture were surprisingly sophisticated and varied. They ate a rich variety of foods, had spacious, well-ventilated living and working quarters, and lavishly decorated many of their ceramic items. Yet Caren was an average farming village, not a seat of the ruling class or a regional center of commerce, archaeologists said. The village of Ceren was rediscovered in 1976 when a bulldozer operator knocked into the wall of one of the structures. Grasses that made up the thatched roof of the dwelling were still preserved, leading an archaeologist to conclude that the structure was recent. After two years, anthropologist Payson D. Sheets of the University of Colorado at Boulder discovered the antiquity of the structures when he dated a sample of thatch to about 1,400 years ago. Sheets was able to survey the site for only a few years before the civil war in El Salvador made it too dangerous to continue. The archaeologists left the site, located northwest of San Salvador, the capital, in 1980 and did not return until 1989. Since then, archaeologists led by Sheets have returned each year. As of spring 1997, they had digged 12 buildings, including a community hall, living quarters, kitchens, storerooms, a religious hall, a sauna, and even a small building believed to be the workplace of a shaman (a priest who uses magic). The smallest objects of daily life were preserved, sometimes as actual organic matter such as seeds or stems, sometimes as impressions in the ash such as that of a cornstalk or a squash. By sending radar signals through the ground in order to detect buried objects, archaeologists in I994 located 22 additional structures still buried in ash. Archaeologists at the site have found the remains of animals including dogs, deer, and a duck tied to a pole. All that remains of the people of Ceren, however, are their footprints, and a few teeth, believed to have been tossed on a roof for good luck. When the teeth were found, workers told Sheets that throwing teeth on the roof is a tradition still practiced by some people in rural El Salvador today. In the eyes of anthropologist Payson D. Sheets, ______.
If you see someone drowning, speed is very important. Once you get him out of the water, if he isn’t breathing, you have four minutes before his brain is completely damaged. Support his neck, tilt his chin upwards. This stops the tongue blocking the air way in the throat and is sometimes enough to get him breathing again. If that doesn’t work, start mouth-to-mouth breathing. Press his nostrils (鼻孔) together with your fingers. Open your mouth wide and take a deep breath. Blow into his lungs until his chest rises, and then remove your mouth and watch his chest fall. Repeat twelve times a minute, keep going until professional help arrives.To bring a child back to life, keep your lips around its mouth and nose and gently blow into its mouth. Give the first four breaths as quickly as possible to fill the blood with oxygen. If, in spite of your efforts, it starts turning blue grey colour, and you can feel no pulse, then pressing its chest is the last chance of saving its life.With arms straight, rock forward, pressing down on the lower half of the breastbones. Don’t be too hard, or you may break a rib (肋骨). Check how effectively you are by seeing if his colour improves or his pulse becomes independent to your chest pressing. If this happens, stop the pressing. Otherwise continue until an ambulance arrives. In doing mouth-to-mouth breathing, you have to ()
Questions 7 to 8 are based on the following news item. At the end of the news item, you will be given 10 seconds to answer each question. Now listen to the news. Which statement is not true
Rabies is an ordinarily infectious disease of the central nervous system, caused by a virus and, as a rule, spread chiefly by domestic dogs and wild flesh-eating animals. Man and all warm-blooded animals are susceptible to rabies. The people of ancient Egypt, Greece and Rome ascribed rabies to evil spirits because ordinarily gently and friendly animals suddenly became vicious and violent without evident cause and, after a period of maniacal behaviour, became paralysed and died. Experiments carried out in Europe in the early nineteenth century of injecting saliva from a rabid dog into a normal dog proved that the disease was infectious. Preventive steps, such as the destruction of stray dogs, were taken and by 1826 the disease was permanently eliminated in Norway, Sweden and Denmark. Though urban centres on the continent of Europe were cleared several times during the nineteenth century, they soon became reinfected since rabies was uncontrolled among wild animals. During the early stages of the disease, a rabid animal is most dangerous because it appears normal and friendly, but it will bite at the slightest provocation. The virus is present in the salivary glands(腺) and passes into the saliva so that the bite of the infected animal introduces the virus into a fresh wound. If no action is taken, the virus may become established in the central nervous system and finally attack the brain. The incubation(潜伏期) period varies from ten days to eight months or more, and the disease develops more quickly the nearer to the brain the wound is. Most infected dogs become restless, nervous, and irritable and vicious, then depressed and paralysed. With this type of rabies, the dog’s death is inevitable and usually occurs within three to five days after the onset of the symptoms. Anti-rabies vaccine(疫苗) is widely used nowadays in two ways. Dogs may be given three-year protection against the disease by one powerful injection, while persons who have been bitten by rabid animals are given a course of daily injections over a week or ten days. The mortality rate from all types of bites from rabid animals has dropped from 9% to 0.5%. In rare cases, the vaccine will not prevent rabies in human beings because the virus produces the disease before the person’s body has time to build up enough resistance. Because of this, immediate vaccination is essential for anyone bitten by an animal observed acting strangely and the animal should be captured circumspectly, and examined professionally or destroyed. Rabies is ______.
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