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Celebrating sleep
World Sleep Day, observed （庆祝）on 21 March, was created to bring attention to the growing number of sleep problems worldwide. Sleep is a natural part of human life, but many people in the modern world ignore its importance. As a result, sleep problems are increasingly common.
In 2002, scientists at the University of Athens in Greece conducted a survey of over 35,000 people in 10 countries around the world, including China, Belgium and South Africa. Of the people, 24 percent said that they did not sleep well, and based on their responses, 31.6 percent were diagnosed (诊断)with insomnia（失眠）and another 17.5 percent were diagnosed with borderline insomnia. In addition, 30.7 percent of survey respondents reported visiting a doctor for help with sleep problems and 11.6 percent said that they felt very sleepy during the day.
Overall, the survey found that many people suffer the effects of poor quality sleep, some examples of which are being unable to fall asleep and waking up in the middle of the night. The main factors causing these problems are pressure from school or work and a fast pace of life, but noise pollution and light pollution also disturb sleep and contribute to poor quality sleep. The survey’s findings are particularly troubling because large numbers of people were found to have difficulty sleeping at night. The short-term effects of this are tiredness and trouble concentrating（专心）. If this happens for a long time, the risk of putting on weight and having a heart attack may increase.
There are many things you can do to improve the quality of your sleep. First, you should have regular sleep habits. Try to go to bed and wake up around the same time each day. You also need to make your bedroom a cool, dark, quiet place to sleep so that heat, light and noise do not disturb you. At night, you should also avoid things that contain caffeine（咖啡因）, such as chocolate, coffee, tea and many soft drinks, as caffeine may keep you from sleeping.
Getting a good night’s sleep is important for everyone. By following the advice above, you can rest better at night and work better during the day.
Title: Celebrating Sleep

Topic	Context
World Sleep Day	People observe Mar. 21, World Sleep Day to bring  ▲  to the problem.
Responses of the survey	Of 3, 5000 people in 10 countries in the world, there were 24 percent of the people saying they didn’t sleep well. 31.6 percent were diagnosed with insomnia and another 17.5 percent were on the borderline of sleeplessness. The percentage of the people  ▲   sleepy during the day is 11.6. 30.7 percent reported    ▲   to a doctor for sleep problems.
Main   ▲   causing sleep problems	Under ▲   from school or work, people may have sleep problems. Noise and light pollution▲ to poor quality sleeps.
Effects of bad quality sleep	Sleepless people may easily  ▲ weight and have a heart attack. Feeling fired and sleepy, people find it ▲to concentrate.
▲   to  take  to improve sleep quality	Have regular sleep habits. Make your bedroom cool, dark and quiet. Avoid things   ▲   caffeine.