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Text 2 Atmospheric pressure can support a column of water up to 10 meters high. But plants can move water much higher: the sequoia tree can pump water to its very top, more than 100 meters above the ground. Until the end of the nineteenth century, the movement of water in trees and other tall plants was a mystery. Some botanists hypothesized that the living cells of plants acted as pumps. But many experiments demonstrated that the stem of plants in which all the cells are killed can still move water to appreciable heights. Other explanations for the movement of water in plants have been based on root pressure, a push on the water from the roots at the bottom of the plant. But root pressure is not nearly great enough to push water to the tops of tall trees. Furthermore, the conifers, which are among the tallest trees, have unusually low root pressures. If water is not pumped to the top of a tall tree, and if it is not pushed to the top of a tall tree, then we may ask: How does it get there According to the currently accepted cohesion-tension theory, water is pulled there. The pull on a rising column of water in a plant results form the evaporation of water at the top of the plant. As water is lost form the surface of the leaves, a negative pressure, or tension, is created. The evaporated water is replaced by water moving from inside the plant in unbroken columns that extend from the top of a plant to its roots. The same forces that create surface tension in any sample of water are responsible for the maintenance of these unbroken columns of water. When water is confined in tubes of very small bore, the forces of cohesion (the attraction between water molecules) are so great that the strength of a column of water compares with the strength of a steel wire of the same diameter. This cohesive strength permits columns of water to be pulled to great heights without being broken. The passage answers which of the following questions
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Part A Read the following texts answer the questions accompany them by choosing A, B, C or D. Mark your answers on ANSWER SHEET 1.Text 1 The British psychoanalyst John Bowlby maintains that separation from the parents during the sensitive "attachment" period from birth to three may sear a child’s personality and predispose to emotional problems in later life. Some people have drawn the conclusion from Bowlby’s work that children should not be subjected to day care before the age of three because of the parental separation it entails, and many people do believe this. But there are also arguments against such a strong conclusion. Firstly, anthropologists point out that the insulated love affair between children and parents found in modern societies does not usually exist in traditional societies. For example, in some tribal societies, such as the Ngoni, the father and mother of a child did not rear their infant alone-far from it. Secondly, common sense tells us that day care would not be so widespread today if parents, care-takers found children had problems with it. Statistical studies of this kind have not yet been carried out, and even if they were, the results would be certain to be complicated and controversial. Thirdly, in the last decade there have been a number of careful American studies of children in day care, and they have uniformly reported that day care had a neutral or slightly positive effect on children’s development. But tests that have had to be used to measure this development are not widely enough accepted to settle the issue. But Bowlby’s analysis raises the possibility that early day care has delayed effects. The possibility that such care might lead to, say, more mental illness or crime 15 or 20 years later can only be explored by the use of statistics. Whatever the long-term effects, parents sometimes find the immediate effects difficult to deal with. Children under three are likely to protest at leaving their parents and show unhappiness. At the age of three or three and a half almost all children find the transition to nursery easy, and this is undoubtedly why more and more parents make use of child care at this time. The matter, then, is far from clear-out, though experience and available evidence indicate that early care is reasonable for infants. Which of the following statements would Bowlby support
Questions 17～20 are based on the following talk. You now have 20 seconds to read Questions 17～20. What does she mean when a middle-aged wife says to a younger one "He is good to you, isn’t he"
Questions 17～20 are based on the following talk. You now have 20 seconds to read Questions 17～20. A working-class wife will, on the whole, obey her husband ______ .
Directions: This section is designed to test your ability to understand spoken English. You will hear a selection of recorded materials and you must answer the questions that accompany them. There are THREE parts in this section: Part A, Part B, and Part C. Remember, while you are doing the test, you should first put down your answers in your test booklet. NOT on the ANSWER SHEET. At the end of the listening comprehension section, you will have 5 minutes to transfer your answers from your test booklet onto ANSWER SHEET 1. If you have any questions, you may raise your hand NOW as you will not be allowed to speak once the test has started. Now look at Part A in your test booklet.Part A You will hear a conversation. As you listen, answer Question 1 to 10 by circling True or False. You will hear the conversation ONLY ONCE. You now have 60 seconds to read Question 1～10. The speaker knows a few Chinese students.
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