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Text 5 The air surrounding us is important to everyone. Without air, we could not exist. Everyone understands that. But air is necessary in many other ways — ways that are not always so obvious or widely known. If we did not have air, there would be no sound. Sound travels through air. Where there is no air, there is no sound. Without air there would be no fire. There would be no automobiles, since motors need air in order to operate. Without air, there would be no wind or clouds. The night time would be very cold and the days very hot. We would be forced to seek shelter from the sun, as there would be no atmosphere to protect us from the sun’s deadly rays. In this huge ocean of air surrounding the earth, there is more energy than in all the coal, oil and gas we have on the earth. Electrical energy is collected in the atmosphere as water is collected and stored in a dam (大坝). The existence of electricity in the air has been known for centuries. Men have gazed in wonder at the bright patterns of lightening in storm clouds. But thorough (彻底的，深入的) study of electricity in the air was not possible until the development of radio. Without air protection, the sun’s rays ______.
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Text 3 Getting a new PC is one thing. Keeping it running smoothly is quite another. While a personal computer should continue to perform well for years, users know that system unsteadiness (不稳定性) does exist. Yet you can reduce it to the smallest amount by following the tips below. First, put in as little software (软件) as possible. You’ll have fewer software-related problems and a system that is easier to manage. Second, you should ensure (确保) that you have as much memory (RAM) in your PC as you need. If you run Windows 98, your computer should have at least 128 megabytes (MB) of RAM and more. You can also get by with 128 MB of RAM if you use Windows NT or Windows 2000, but these operating systems will run much more smoothly if you have 256 MB of RAM or more. Third, make sure you buy good hardware (硬件). No-name products may be cheaper and sometimes just as good as name-brand products, but name-brand products usually become well-known because Windows will more often support the hardware that you buy. If you are starting out with computers, it’s also a good idea to buy ready- made systems from major manufactures (制造商). They are likely to have been tested thoroughly with your operating system, and you will generally experience fewer problems. Fourth, do prepare for disaster. No matter how well your system runs when you get it, the day will come when it will need to be replaced. Hopefully (但愿), you will replace it because technology has become out-dated, but you may need to replace it also because the hard drive crashes (毁坏) or you begin experiencing problems that no one can figure out. That’s why it’s important to copy your important information regularly. Whether you use a tape backup device or a CD-ROM drive, it’s important to make a regular backup plan and stick to it. What is the main purpose of this passage
What kind of films does the man like
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第一节 单项填空 从A、B、C、D四个选项中，选出可以填入空白处的最佳选项。 She ______ several jackets and finally picked out a blue one.
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