【文章內(nèi)容簡介】 fort in the shoulders, upper middle back and neck. Disfort in these parts of your back is consistent with upper back pain. In most situations bad posture is responsible. This is often because we spend long periods of time sitting or standing in the same position, generally in our place of work or study. By maintaining the same posture all the time, the muscles in the upper back which connect the shoulders and help to keep our back straight bee tense, stiff and painful. Other causes of upper back pain include over enthusiastic physical exercise and, most monly, heavy lifting which is carried out incorrectly, . without bending the knees。 keeping the back straight, ect.. Physical exercise should not be stopped because of upper back pain. Indeed it is an excellent method to prevent this problem from being worse. There are many other types of exercises which can be helpful such as jogging or walking either using a treadmill(踏車)at home or out in the streets. Swimming is an ideal exercise because it uses all the body’s muscles. When you are swimming above water, the weight of your body is supported by the water, which means your muscles and spine(脊柱)can relax and stretch out and thus ease upper back pain. The best way to avoid upper back pain is to try to avoid sitting or standing in the same position for extended periods. If it is possible, try to have a stretch break every hour or so. You should try to find ways to jog your memory throughout the day to keep your posture correct —put little notes around your puter screen to remind you! It will eventually e naturally, and hopefully the problem will disappear.60. If you have upper back pain, you ____. A. should have a break and take a walk every hour B. go to the hospital for physical treatment as soon as possibleC. should learn to swim to help your muscles relaxD. can do some exercises to make your muscles more flexible61. Back pain is probably NOT caused by _______. A. standing or sitting for long periods of time B. doing too much physical exercise C. keeping your back straight when lifting heavy things D. stretching out and bending your knees 62. The underlined word jog in the last paragraph probably means _____.A. to run slowly B. to give a slight pushC. to keep considering something D. to make somebody remember something63. In the last paragraph, the author mainly _______. A. introduces the key points necessary in avoiding upper back painB. talks about how to do exercises regularlyC. provides a number of methods you can use to remember thingsD. proposes ways we can keep correct postureCScientists from the University of Sheffield and Queen’s University Belfast have made a unique research which will help us understand one of the most puzzling features of the Sun. This research has helped explain why the outside atmosphere of the Sun is actually hotter than the inner. The surface of the Sun, known as the photosphere(光球), reaches a temperature of 5,000 degrees。 however, the outer atmosphere, known as the corona(日冕), can reach a temperature of over a million degrees. The study, which has been published in the Science journal, has discovered evidence for the existence of a new kind of solar wave, called the Alfv233。n wave, which transports energy to heat the Sun’s corona. The scientists used data from the Swedish Solar Telescope to detect for the first time these waves in the Sun’s lower atmosphere. This telescope is the largest and most powerful solar telescope in Europe and is able to produce some of the sharpest images currently available. Professor Robert from the University of Sheffield said, These waves, once detected, can be used to determine the physical conditions in the invisible regions of the Sun and other stars. Dr. Daivd Jess, lead researcher on the project from Queen’s University Belfast, said, Often, waves can be visualized(想象) by the rippling of water when a stone is dropped into a pond. However, Alfv233。n waves cannot be seen easily. In fact, they are pletely invisible to the naked eye. Only by examining the motions of structures and their corresponding velocities(速度)in the Sun’s atmosphere could we find, for the first time, the presence of these Alfv233。n waves. The scientists all agreed that understanding solar activity and its influence on the Earth’s climate is of great importance to humankind. The Sun is not as 39。quiet’as many people think. The solar corona, visible from the Earth only during a total solar eclipse(日全食), is a very dynamic environment which can erupt suddenly, releasing more energy than 10 billion atomic bombs. 64. What have the scientists achieved in their study? A. They’ve discovered the difference between photosphere and corona B. They’ve explained the features of the sun clearly.C. They’ve discovered a new kind of solar wave.D. They’ve detected the exact temperatures of the sun’s surface.65. Which of the following are properties of the Alfv233。n wave?a. It is a kind of solar wave.b. It can transport energy. c. It was detected by Swedish scientists for the first time. d. It cannot be seen by the naked eye.e. It exists in the shape of rippling of water. A. acd B. abd C. bcd D. cde66. We can learn from the passage that ________. A. the Swe