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第三篇Renewable Energy SourcesToday petroleum (石油)provides around 40% of the world’s energy needs, mostly fuelling automobiles. Coal is still used, mostly in power stations, to cover one-quarter of our energy needs, but it is the least efficient, unhealthiest and most environmentally damaging fossil fuel(矿物燃料). Natural gas reserves could fill some of the gap from oil, but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years. Less polluting renewable energy sources offer a more practical long-term energy solution. "Renewable" refers to the fact that these resources are not used faster than they can be replaced.Hydroelectric(水力发电的) power is now the most common form of renewable energy, supplying around 20% of world electricity. China’s Three Gorges Dam is the largest ever. At five times the size of the US’s Hoover Dam, its 26 turbines(涡轮机) will generate the equivalent energy of 18 coal-fired power stations. It will satisfy 3% of China’s entire electricity demand.In 2003, the first commercial power station to use tidal (潮汐的)currents in the open sea opened in Norway. It is designed like windmill (风车), but others take the form of turbines.As prices fall, wind power has become the fastest growing type of electricity generation-quadrupling (翻两番)worldwide between 1999 and 2005. Modem wind farms consist of turbines that generate electricity. Though it will be more expensive, there is more than enough wind to provide the world’s entire energy needs. Wind farms come in onshore and offshore forms. They can often end up at spots of natural beauty, and are often unpopular with residents. And turbines are not totally harmless, they can interfere with radar, alter climate and kill sea birds. Scotland is building Europe’s largest wind farm, which will power 200, 000 homes. The UK’s goal is to generate one-fifth of power from renewable sources, mainly wind, by 2020. But this may cause problems, because wind is unreliable. According to the passage, resources like wind are（）.
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A. that person’s health B. a scientific answer C. scientific researchers D. the genes E. the function F. the size Genetic mutations in a person’s genome may affect______.
在填制入境货物报检单时，进口货物的品名应与进口合同一致，但废旧货物应在品名中特别注明。（）
An Intelligent CarDriving needs sharp eyes, keen ears, quick brain, and coordination(协调) between hands and the brain. Many human drivers have all (51) and can control a fast-moving ear. But how does an intelligent car control itself?There is a virtual(虚拟) driver in the smart car. This virtual driver has "eyes", "brains", "hands" and "feet" too. The minicameras (52) each side of the ear are his "eyes" which (53) the road conditions ahead of it. They watch the (54) to the car’s left and right. There is also a highly automatic driving (55) in the car. It is the built-in computer, which is the virtual driver’s "brain". His "brain" (56) the speeds of other moving cars near it and analyzes their positions. Basing on this information, it chooses the (57) path for the intelligent ear, and gives instructions to the "hands" and "feet" to act accordingly. In this way, the virtual driver (58) his car.What is the virtual driver’s best advantage He reacts (59) . The minicameras are bringing (60) continuously to the "brain". It completes the processing of the images with-in 100 milliseconds. (61) , the world’s best driver needs at least one second to react. Besides, when he takes (62) , he needs one more second.The virtual driver is really wonderful. He can reduce the accident (63) considerably on expressways(高速公路). In this (64) , can we let him have the wheel at any time and in any place Experts (65) that we cannot do that just yet. His ability to recognize things is still limited. He can now only drive an intelligent car on expressways. 51（）
Unlocking the Human Genome (基因组)1 A project to unlock secrets--what scientist could resist that challenge This is what many scientists are doing as they work on the Human Genome Project. The aim of the project is to decode (破译) all of the some 100,000 genes in the human body. Scientists are using DNA fingerprinting techniques to do the decoding.2 DNA is the substance found in the chromosomes(染色体)of a cell. A chromosome is a chain of genes. Each gene carries a piece of genetic information. At any one moment in a cell, thousands of genes are turned on and off to produce proteins (蛋白质). The challenge for scientists is to find out what role each gene plays in protein production. At some point this decoding will be complete. Then scientists will have a map of an ideal genome, or a picture of the total genetic nature of a human being. The ideal genome is called a consensus(交感)genome. Everything works well in a consensus genome.3 But no one in the world has a consensus genome. Everyone’s genome is different from the ideal. These differences are referred to as genetic mutations(突变). Genetic mutations in a person’s genome mean that the person has a greater than average chance of suffering from health problems. Some problems are not life-threatening. These would include things like colorblindness, or mild headaches. Other problems are serious, such as heart disease or cancer.4 It will take years to identify the role of each of the 100,000 genes. The short-term goal of the project is to find the physical and mental health problems a person is likely to encounter during his or her lifetime. The long-term goal is to have each person live a longer, healthier life.A. How does DNA workB. What is the Human Genome Project aboutC. How are the DNA samples collectedD. What are the goals of the Human Genome ProjectE. What is the role of each geneF. What are the consequences of genetic mutations Paragraph 3（）
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