题目内容
Plants and Mankind Botany, the study of plants, occupies a peculiar position in the history of human knowledge. We don’t know what our Stone Age ancestors knew about plants, but from what we can observe of preindustrial societies that still exist, a detailed learning of plants and their properties must be extremely ancient. This is logical. Plants are the basis of the food pyramid for all living things, even for other plants. They have always been enormously important to the welfare of people, not only for food, but also for clothing, weapons, tools, dyes, medicines, shehers, and many other purposes. Tribes living today in the jungle of the Amazon recognize hundreds of plants and know many properties of each. To them botany has no name and is probably not even recognized as a special branch of "knowledge" at all. Unfortunately, the more industrialized we become the farther away we move from direct contact with plants, and the less distinct our knowledge of botany grows. Yet everyone comes unconsciously on an amazing amount of botanical knowledge, and few people will fall to recognize a rose, an apple, or an orchid. When our Neolithic ancestors, living in the Middle East about 10,000 years ago, discovered that certain grasses could be harvested and their seeds planted for richer yields the next season, the first great step in a new association of plants and humans was taken. Grains were discovered and from them flowed the marvel of agriculture: cultivated crops. From then on, humans would increasingly take their living from the controlled production of a few plants, rather than getting a little here and a little there from many varieties that grew wild and the accumulated knowledge of tens of thousands of years of experience and intimacy with plants in the wild would begin to fade away. People can not survive without plants.
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More Than 8 Hours Sleep Too Much of a Good Thing 1. Although the dangers of too little sleep are widely known, new research suggests that people who sleep too much may also suffer the consequences. 2. Investigators at the University of California in San Diego found that people who clock up 9 or 10 hours each weeknight appear to have more trouble falling and staying asleep, as well as a number of other sleep problems, than people who sleep 8 hours a night. People who slept only 7 hours each night also said they had more trouble falling asleep and feeling refreshed after a night’s sleep than 8-hour sleepers. 3. These findings, which DL Daniel Kripke reported in the journal Psychosomatic Medicine, demonstrate that people who want to get a good night’s rest may not need to set aside more than 8 hours a night. He added that "it might be a good idea" for people who sleep more than 8 hours each night to consider reducing the amount of time they spend in bed, but cautioned that more research is needed to confirm this. 4. Previous studies have shown the potential dangers of chronic shortages of sleep—for instance, one report demonstrated that people who habitually sleep less than 7 hours each night have a higher risk of dying within a fixed period than people who sleep more. 5. For the current report, Kripke reviewed the responses of 1,004 adults to sleep questionnaires, in which participants indicated how much they slept during the week and whether they experienced any sleep problems. Sleep problems included waking in the middle of the night, arising early in the morning and being unable to fall back to sleep, and having fatigue interfere with day-to-day functioning. 6. Kripke found that people who slept between 9 and 10 hours each night were more likely to report experiencing each sleep problem than people who slept 8 hours. In an interview, Kripke noted that long sleepers may struggle to get rest at night simply because they spend too much time in bed. As evidence, he added that one way to help insomnia is to spend less time in bed. "It stands to reason that if a person spends too long a time in bed, then they’ll spend a higher percentage of time awake," he said. A. Kripke’s Research Tool B. Dangers of Habitual Shortages of Sleep C. Criticism on Kripke’s Report D. A Way of Overcoming Insomnia E. Sleep Problems of Long and Short Sleepers F. Classification of Sleep Problems Paragraph 4 ______
在软土地基上直接填筑路堤，应符合的规定有______。
More Than 8 Hours Sleep Too Much of a Good Thing 1. Although the dangers of too little sleep are widely known, new research suggests that people who sleep too much may also suffer the consequences. 2. Investigators at the University of California in San Diego found that people who clock up 9 or 10 hours each weeknight appear to have more trouble falling and staying asleep, as well as a number of other sleep problems, than people who sleep 8 hours a night. People who slept only 7 hours each night also said they had more trouble falling asleep and feeling refreshed after a night’s sleep than 8-hour sleepers. 3. These findings, which DL Daniel Kripke reported in the journal Psychosomatic Medicine, demonstrate that people who want to get a good night’s rest may not need to set aside more than 8 hours a night. He added that "it might be a good idea" for people who sleep more than 8 hours each night to consider reducing the amount of time they spend in bed, but cautioned that more research is needed to confirm this. 4. Previous studies have shown the potential dangers of chronic shortages of sleep—for instance, one report demonstrated that people who habitually sleep less than 7 hours each night have a higher risk of dying within a fixed period than people who sleep more. 5. For the current report, Kripke reviewed the responses of 1,004 adults to sleep questionnaires, in which participants indicated how much they slept during the week and whether they experienced any sleep problems. Sleep problems included waking in the middle of the night, arising early in the morning and being unable to fall back to sleep, and having fatigue interfere with day-to-day functioning. 6. Kripke found that people who slept between 9 and 10 hours each night were more likely to report experiencing each sleep problem than people who slept 8 hours. In an interview, Kripke noted that long sleepers may struggle to get rest at night simply because they spend too much time in bed. As evidence, he added that one way to help insomnia is to spend less time in bed. "It stands to reason that if a person spends too long a time in bed, then they’ll spend a higher percentage of time awake," he said. A. Kripke’s Research Tool B. Dangers of Habitual Shortages of Sleep C. Criticism on Kripke’s Report D. A Way of Overcoming Insomnia E. Sleep Problems of Long and Short Sleepers F. Classification of Sleep Problems A. fall asleep again B. become more energetic the following day C. sleep less than 7 hours D. confirm those serious consequences E. suffer sleep problems F. sleep more than 8 hours To get a good night’s rest, people may not need to ______.
以下药物中，治疗慢性阻塞性肺病最主要的药物是
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