The need to feed a growing population is putting much pressure on the world's supply of water. With 97% of the world's water too salty to be drunk or used in agriculture, the worldwide supply of water needs careful management, especially in agriculture. Although the idea of a water shortage(短缺)seems strange to someone fortunate enough to live in a high rainfall country, many of the world's agricultural industries experience constant water shortages.

    Although dams can be built to store water for agricultural use in dry areas and dry seasons, the costs of water redistribution(重新分配)are very high. Not only is there the cost of the engineering itself, but there is also an environmental cost to be considered. Where valleys(山谷)are flooded to create dams, houses are lost and wildlife homes destroyed. Besides, water may flow easily through pipes to fields, but it cannot be transported from one side of the world to the other. Each country must therefore rely on the management of its own water to supply its farming requirements. This is particularly troubling for countries with agricultural industries in areas dependent on irrigation. In Texas, farmers' overuse of irrigation water has resulted in a 25% reduction of the water stores.

    In the Central Valley area of southwestern USA, a huge water engineering project provided water for farming in dry valleys, but much of the water use has been poorly managed.

    Saudi Arabia's attempts to grow wheat in desert areas have seen the pumping of huge quantities of irrigation water from underground reserves. Because there is no rainfall in these areas, such reserves can only decrease, and it is believed that fifty years of pumping will see them run dry.

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    In many businesses, computers have largely replaced paperwork, because they are fast, and do not make mistakes. And they are honest. Many banks say that their business is “untouched by human hands” and therefore safe. But they have no thought that the growing number of computer crimes (犯罪) show they can be used to steal.

    Computer criminals (罪犯) don't use guns. And even if they are caught, it is hard to punish them because there is often no proof. A computer cannot remember who used it. It simply does what it is told. The head teller(出纳主管) at a New York City bank used a computer to steal more than one and a half billion dollars in just four years. No one noticed this because he moved the money from one account (账户) to another. Each time a customer whose money he had stolen questioned the balance in his account, the teller said it was a computer mistake, then replaced the missing money from someone else's account. This man was caught at last.

    Some workers use the computer's power to punish their bosses they consider unfair. Recently, a large company fired its computer record assistant for reasons that were connected with her personal life rather than her job. She was given thirty days notice. In those thirty days, she stole all the company's computerized records.

    Most computer criminals have been common workers. Now police wonder if this is “the tip of iceberg”. As one official says, “I have the feeling that there is more crime out there than we are catching. What we are seeing now is all so poorly done. I wonder what the real experts are doing—the ones who really know a computer works.”

    Hiring a self-drive car really adds to the enjoyment of your holiday. There are so many places of interest to visit. And if you enjoy seeing more than just the city centre, there's no better way to explore than by car.

    Conditions of Hire

    ⒈The shortest rental period at these especially low prices is three days. For prices and for periods of one or two days you only see our representative at the hotel.

    ⒉Car hire must be booked six weeks or more before arrival in London to guarantee a car. But if you have been unable to make a booking in advance, please see our representative at the hotel who may still be ab le to help you.

    ⒊The car types on the sheet are examples of the types of cars in each price range, but a particular car cannot be guaranteed.

    ⒋Upon delivery the driver(s) will be asked to sign the car hire company's Conditions of Hire.

    ⒌If you decide to hire a car, just fill in the Booking Form and return it to us. A booking fee of ￡12 as part of the car hire cost is required.

    ⒍Should you be forced to cancel your car hire booking after payment in full (two weeks before date of hire), a cancellation charge of ￡12 will be made.

    Why do people lie? Many psychologists agree that lying can start from childhood. There are various reasons why children make false statements. They usually tell untruthful stories to cover up the mistakes that they have done in the past. Lying is also a way to avoid receiving punishments from parents. If parents fail to reprimand their children for making up false stories, then there is a possibility that they will continue to lie during their teenage years.

    Teenagers lie because they want to be accepted by their friends. This is the main reason why they create stories that are not true just to become presentable and acceptable to other people. In some instances, teenagers tell untruthful statements to avoid criticisms from their families and friends.

    As teenagers grow, lying becomes one of their habits. Their knowledge on making up untruthful stories becomes more developed. People lie in workplaces if they fail to meet the deadlines and if they fail to accomplish and do their tasks efficiently. Some of the common lies made in workplaces are getting sick and having emergencies at home. The danger involved in frequent lying is when it becomes a character. Frequent lying causes the development of the condition known to doctors as pathological(病态的) lying.

    Pathological lying is a mental health condition, which is associated with individuals who have the urge to tell untruthful statements. Patients suffering from it make up stories about everything and anything. These individuals pretend to meet the standards of other people who they want to please. These patients cheat other people because it gives them an unexplained pleasure. One of the best ways of treating pathological liars is to help them tell true statements and stories at all times. This may be hard for them, but as they are accustomed to it, they will start to realize that they will be more accepted by their families and other people if they stop themselves from making up false stories.

    NOT all memories are sweet. Some people spend all their lives trying to forget bad experiences. Violence and traffic accidents can leave people with terrible physical and emotional scars. Often they relive these experiences in nightmares.

    Now American researchers think they are close to developing a pill, which will help people forget bad memories. The pill is designed to be taken immediately after a frightening experience. They hope it might reduce ,or possibly erase(抹去),the effect of painful memories.

    In November, experts tested a drug on people in the US and France. The drug stops the body releasing chemicals that fix memories in the brain. So far the research has suggested that only the emotional effects of memories may be reduced, not that the memories are erased.

    The research has caused a great deal of argument. Some think it is a bad idea, while others support it.

    Supporters say it could lead to pills that prevent or treat soldiers' troubling memories after war. They say that there are many people who suffer from terrible memories.

    "Some memories can ruin people's lives. They come back to you when you don't want to have them in a daydream or nightmare. They usually come with very painful emotions," said Roger Pitman, a professor of psychiatry at Harvard Medical School. "This could relieve a lot of that suffering."

    But those who are against the research say that changing memories is very dangerous because memories give us our identity (特质). They also help us all avoid the mistakes of the past.

    "All of us can think of bad events in our lives that were horrible at the time but make us who we are. I'm not sure we want to wipe those memories out, "said Rebecca Dresser, a medical ethicist.