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Do you agree or disagree with the following statement ？The government should require all young adults to perform some kind of national service, such as military service or social work.Use specific reasons and details to support your answer.
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碧云寺内的罗汉堂是仿______而建，室内共有罗汉______尊。P37
Set 3THE SENSE OF SMELL1.Smell is the most direct of all the senses. It is thought to be the oldest sense in terms of human evolution, which may explain why smell is hard-wired into the brain. The olfactory nerve, which manages the perception of smells, is essentially an extension of the brain. The olfactory nerve provides a direct link from receptors at the top of the nose to the portion of the brain that controls memory, emotion, and behavior.2.The olfactory system detects certain airborne chemicals that enter the nose and then transmits this chemical information to the limbic system in the brain. The olfactory region at the upper end of each nostril is yellow, moist, and full of fatty substances. The shade of yellow indicates the strength of the sense of smell: the deeper the shade, the keener and more acute it is. Animals have a very strong sense of smell, so their olfactory regions are dark yellow to reddish brown, while those of humans are light yellow.3.When an odorous substance enters the nose, it binds to olfactory receptor cells, the neurons lining the yellow upper portion of the nasal cavity. Olfactory receptor cells contain microscopic hairs called cilia that extend into the layer of mucus coating the inside of the nose. Odor molecules diffuse into this region and are absorbed by the cilia of the olfactory receptor cells. What this means is that when we hold a rose to our nose and inhale, odor molecules float up into the nasal cavity, where they are absorbed by five million olfactory receptor cells. The receptor cells alert the olfactory nerve, which sends impulses to the brain’s olfactory bulb, or smell center. Thus, olfactory information about the rose enters the brain’s limbic system, where, in most of us, it stimulates a feeling of pleasure.4.The limbic system of the brain integrates memory, emotion, and behavior. The system is composed of a group of related nervous system structures that are the functional center of emotions such as anger, fear, pleasure, and sadness. The components of the limbic system are linked to the cerebral cortex, the part of the brain involved in complex learning, reasoning, and personality. The cerebral cortex makes decisions about the emotional content of these unique human qualities after "consulting" the limbic system and other brain centers in processing and retrieving memories. It may, in turn, use memories to modify behavior.5.Scent may be the strongest trigger of memory and emotions. When we inhale a scent, receptors in the brain’s limbic center compare the odor entering our nose to odors stored in our memory. Along the way, memories associated with those odors are stimulated. A smell can be overwhelmingly nostalgic because it triggers powerful images and emotions. The waxy fragrance of crayons can instantly transport us to our second-grade classroom, or the scent of freshly mown grass can flood us with the joy of summer freedom. What we see and hear may fade quickly in short-term memory, but what we smell is sent directly to long-term memory.6.Smells can increase alertness and stimulate learning and retention. In one study, children memorized a word list, which was presented both with and without accompanying scents. The children recalled words on the list more easily and with higher accuracy when the list was given with scents than without, showing the link between smell and the ability to retain information. In another study, researchers examined how various smells can increase alertness and decrease stress. They found that the scent of lavender could wake up the metabolism and make people more alert. They also found that the smell of spiced apples could reduce blood pressure and avert a panic attack in people under stress.Glossary:nostalgic: causing a desire for things, persons, or situations of the past; causing homesicknessretention: the act of retaining; keeping, holding, or maintaining What can be inferred from paragraph 6 about learning ？（）
Some people like to cook their own meals at home. Others prefer to eat in a restaurant or a cafeteria.Which do you prefer and why Include details and examples in your explanation.
Set 5THE DOMESTICATION OF ANIMALS1.The domestication of wild species led directly to denser human populations by yielding more food than the hunter-gatherer lifestyle could provide. In societies that possessed domestic animals, livestock helped to feed more people by providing meat, milk, and fertilizer, and by pulling plows. Large domestic animals became the societies’ main source of animal protein, replacing wild game, and they also furnished wool, leather, and land transport. Humans have domesticated only a few species of large animals, with "large" defined as those weighing over 100 pounds (45 kilograms). Fourteen such species were domesticated before the twentieth century, all of them terrestrial mammals and herbivores. The five most important of these are sheep, goats, pigs, horses, and cattle or oxen.2.Small animals such as ducks, geese, rabbits, dogs, cats, mink, bees, and silkworms have also been domesticated. Many of these small animals provided food, clothing, or warmth. However, none of them pulled plows or wagons, none carried riders, and none except dogs pulled sleds. Furthermore, no small domestic animals have been as important for food as have large domestic animals.3.Early herding societies quickly domesticated all large mammal species that were suitable for domestication. There is archaeological evidence that these species were domesticated between 10,000 and 4,500 years ago, within the first few thousand years of the origins of farming-herding societies after the last Ice Age. The continent of Eurasia has been the primary site of large mammal domestication. Having the most species of wild mammals to begin with, and losing the fewest to extinction in the last 40,000 years, Eurasia has generated the most candidates for domestication.4.Domestication involves transforming wild animals into something more useful to humans. Truly domesticated animals differ in many ways from their wild ancestors. These differences result from two processes: human selection of individual animals that are more useful to humans than other individuals of the same species, and evolutionary responses of animals to the forces of natural selection operating in human environments rather than in wild environments.5.To be domesticated, a wild species must possess several characteristics. A candidate for domestication must be primarily a herbivore because it takes less plant biomass to feed a plant eater than it does to feed a carnivore that consumes plant eaters. No carnivorous mammal has ever been domesticated for food simply because it would be too costly. A candidate must not only weigh an average of over 100 pounds but also grow quickly. That eliminates gorillas and elephants, even though they are herbivores. Moreover, candidates for domestication must be able to breed successfully in captivity.6.Since almost any sufficiently large mammal species is capable of killing a human, certain qualities disqualify a wild animal for domestication. The animal cannot have a disposition that is nasty, dangerous, or unpredictable—characteristics that eliminate bears, African buffaloes, and some species of wild horses. The animal cannot be so nervous that it panics around humans. Large herbivorous mammal species react to danger from predators or humans in different ways. Some species are nervous, fast, and programmed for instant flight when they perceive danger. Others are less nervous, seek protection in herds, and do not run until necessary. Most species of deer and antelope are of the former type, while sheep and goats are of the latter.7.Almost all domesticated large mammals are species whose wild ancestors share three social characteristics: living in a herd, maintaining a dominance hierarchy in the herd, and having herds that occupy overlapping home ranges instead of mutually exclusive territories. Humans have taken advantage of these characteristics in keeping domestic animals together with others of their species and in close proximity to other species of domestic animals.Glossary:terrestrial: living on land rather than in waterherbivores: animals that feed mainly on plants Read the first sentence of a summary of the passage. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage.This question is worth 2 points.Answer ChoicesA．The most important domestic animals are large herbivorous mammals that live in herds.B．Ducks,geese,rabbits,dogs,cats,and many other small animals have been domesticated.C．Although herbivores eat mainly plant matter,some species occasionally eat small animals.D．Humans quickly domesticated all large mammal species that were suitable for domestication.E．Animals must have several essential characteristics in order to be domesticated successfully.F．Large herbivorous mammals respond in various ways when threatened by predators.The domestication of animals provided humans with food, clothing, and other benefits.·____________________________________________________________·____________________________________________________________·____________________________________________________________
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