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Directions: There are 4 reading passages in this part. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice and mark your answer on the ANSWER SHEET by blackening the corresponding letter in the brackets.Passage One All animals must rest, but do they really sleep as we know it The answer to this question seems obvious. If an animal regularly stops its activities and stays quiet and unmoving - if it looks as though it is sleeping - then why not simply assume that it is in fact sleeping But how can observers be sure that an animal is sleeping They can watch the animal and notice whether its eyes are open or closed, whether it is active or lying quietly, and whether it responds to light or sound. These factors are important clues, but they often are not enough. Horses and cows, for example, rarely close their eyes, and fish and snakes cannot close them. Yet this does not necessarily mean that they do not sleep. Have you ever seen a cat dozing with an eye partly open Even humans have occasionally been observed to sleep with one or both eyes partially open. Animals do not necessarily lie down to sleep either. Elephants, for example, often sleep standing up, with their tusks resting in the fork of a tree. Finally, while "sleeping" animals often seem unaware of changes in the sounds and light and other stimuli around them, that does not really prove they are sleeping either. Observations of animal behavior alone cannot fully answer the question of whether or not animals sleep. The answers come from doing experiments in "sleep laboratories" using a machine called the electroencephalograph (EEC). The machine is connected to animals and measures their brain signals, breathing, heartbeat, and muscle activity. The measurements are different when the animals appear to be sleeping than when they appear to be awake. Using the EEC, scientists have confirmed that all birds and mammals studied in laboratories do sleep. There is some evidence that reptiles, such as snakes and turtles, do not truly sleep, although they do have periods of rest each day, in which they are quiet and unmoving. They also have discovered that some animals, like chimpanzees, cats, and moles (who live underground), are good sleepers while others, like sheep, goats, and donkeys, are poor sleepers. Interestingly, the good sleepers are nearly all hunters with resting places that are safe from their enemies. Nearly all the poor sleepers are animals hunted by other animals: they must always be watching for enemies, even when they are resting. The statement, "Horses and cows, for example, rarely close their eyes" aims to show that ______.
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Directions: There are 4 reading passages in this part. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice and mark your answer on the ANSWER SHEET by blackening the corresponding letter in the brackets.Passage One All animals must rest, but do they really sleep as we know it The answer to this question seems obvious. If an animal regularly stops its activities and stays quiet and unmoving - if it looks as though it is sleeping - then why not simply assume that it is in fact sleeping But how can observers be sure that an animal is sleeping They can watch the animal and notice whether its eyes are open or closed, whether it is active or lying quietly, and whether it responds to light or sound. These factors are important clues, but they often are not enough. Horses and cows, for example, rarely close their eyes, and fish and snakes cannot close them. Yet this does not necessarily mean that they do not sleep. Have you ever seen a cat dozing with an eye partly open Even humans have occasionally been observed to sleep with one or both eyes partially open. Animals do not necessarily lie down to sleep either. Elephants, for example, often sleep standing up, with their tusks resting in the fork of a tree. Finally, while "sleeping" animals often seem unaware of changes in the sounds and light and other stimuli around them, that does not really prove they are sleeping either. Observations of animal behavior alone cannot fully answer the question of whether or not animals sleep. The answers come from doing experiments in "sleep laboratories" using a machine called the electroencephalograph (EEC). The machine is connected to animals and measures their brain signals, breathing, heartbeat, and muscle activity. The measurements are different when the animals appear to be sleeping than when they appear to be awake. Using the EEC, scientists have confirmed that all birds and mammals studied in laboratories do sleep. There is some evidence that reptiles, such as snakes and turtles, do not truly sleep, although they do have periods of rest each day, in which they are quiet and unmoving. They also have discovered that some animals, like chimpanzees, cats, and moles (who live underground), are good sleepers while others, like sheep, goats, and donkeys, are poor sleepers. Interestingly, the good sleepers are nearly all hunters with resting places that are safe from their enemies. Nearly all the poor sleepers are animals hunted by other animals: they must always be watching for enemies, even when they are resting. According to the research findings mentioned in the passage, reptiles ______.
S5. At what moment does a fight between male bettas start
Passage Four In most American cities, the tent for a one-bedroom apartment was $250 or more per month in recent years. In some smaller cities such as Louisville, Kentucky or Jacksonville, Florida the rent was less, but in larger cities it was more. For example, if you lived in Los Angeles, you had to pay $400 or more to rent a one-bedroom apartment, and the same apartment rented for $625 and up in Chicago. The most expensive rents in the U. S. were in New York City, where you had to pay at least $700 a month to rent a one-bedroom apartment in most parts of the city. Renters and city planners are worried about the high cost of renting apartments. Many cities now have rent-control laws to keep the cost of renting low. These laws help low-income families who cannot pay high rents. Rent control in the United States began in 1943 when the government imposed rent controls on all American cities to help workers and the families of soldiers during World War II. After the war, only one city—New York—continued these World War II controls. Recently, more and more cities have returned to rent controls. At the beginning of the 1980s, nearly one fifth of the people in the United States lived in cities with rent-control laws. Many cities have rent-control laws, but why are rents so high Builders and landlords blame rent controls for the high rents. Rents are high because there are not enough apartments to rent, and they blame rent controls for the shortage of apartments. Builders want more money to build more apartment buildings, and landlords want more money to repair their old apartment buildings. But they cannot increase rents to get this money because of the rent-control laws. As a result, landlords are not repairing their old apartments, and builders are not building new apartment buildings to replace the old apartment buildings. Builders are building apartments for high-income families, not low-income families, so low-income families must live in old apartments that are in disrepair. Builders and landlords claim that rent-control laws really hurt low-income families. Many renters disagree with them. They say that rent control is not the problem. Even without rent controls, builders and landlords will continue to ignore low-income housing because they can make more money from high-income housing. The only answer, they claim, is more rent controls and government help for low-income housing. From the passage we learn that many renters disagree with ______.
阅读下面短文，回答下列五遭题。 2001年3月15日，北京大学教授于希贤来到抚仙湖，并组织考察组乘坐潜水器潜入湖底。他们利用声纳技术在水深15米处发现第一个目标。有一堵石墙，石料大小不一，每个石块上至少有一面到两面是平整的，带有人工加工过的痕迹。从声纳图上可以看到，该建筑区还具有中轴线和类似普通城市里的“一般居民居住区”，从建筑特点看，它们带有明显的当地黎族的古代建筑风格。没有多久，声纳图上又发现新的目标。潜水器掉头搜寻，发现了一大片呈正南北向建造的建筑群落。群落不大，但石料加工更精细。石料三面都有加工的痕迹，十分平整精细，另外所有散落的石块都是有序地排列的。这一区域还有数米宽的南北向石板大道。从这些可以看出，那个时代有相当高的文化水准。于教授推测，这里可能是古城的“富人区”。绕过石质城墙后，便是所谓的“贫民区”。 于教授说，通过对湖周围地区地理地质环境的考察和比较，可以肯定这座古城是在一次巨大的自然灾害中陷落湖底的。该建筑群依山傍水，位于小江断裂带西支的深断裂带上。公元110年东汉时期这里曾经发生过一次大地震。于教授还说，尽管古城的年代还需要进一步确定，但是有一点可以肯定——抚仙湖底确实有一座陷落的古滇时期建筑群落，且已经初具城市功能，因为具有不同级别的建筑群是判断是否构成城市的重要指标。该遗址面积有2.4平方公里，比世界著名的“庞贝古城”还要大。由于水下考察时没有发现任何动植物残骸及陶瓷、砖瓦的残片，这给探测年代带来了相当的困难，但从水下建筑群石料的打制方式来看，湖中古城与滇中发现的长城颇为相似，应与其处于同一时代，即距今约两千年前。 文中画线句子“没有多久，声纳图上又发现新的目标”中“目标”是( )。
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