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问题 选择题
命题“∀x＞0，x2+x＞O“的否定是（　　）
A．∃x＞0，使得x2+x＞0B．∃x＞0，x2+x≤0
C．∀x＞0，都有x2+x≤0D．∀x≤0，都有x2+x＞0
答案

答案：B

单项选择题

以( )为标志的环境热潮推动下。生态城市的概念得到了世界各国的普遍关注和接受。

A．《我们共同未来》

B．《21世纪议程》

C．《伊斯坦布尔宣言》

D．《里约热内卢宣言》
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Part 2


Questions 9-18


·Read the following article and answer questions 9-18 on the next page.

Train Your Body into Knowing When It’s Time to Sleep


1. A good night’s sleep actually starts in the morning. The second your eyes open, light shoots down the optic nerve and into the brain’s biological clock. There it stimulates the production of hormones that regulate growth, reproduction, eating, sleeping, thinking, remembering—even how you feel from minute to minute. "Sunlight activates the brain," says Frisca L. Yan-Go, M.D., medical director of the UCLA Sleep Disorders Center. And activating it at the same time every morning synchronizes your body’s biological clock. Then your body has a clear direction that at midnight it’s supposed to be asleep and at noon it’s supposed to be awake. Wake up at a different time every day and the clock is out of order. You feel sleepy and hung over for hours, and even when you start to feel a bit more alert after that first Starbucks (星巴克) , you really never achieve the mental edge of what you’re capable.
2. Shall we go to bed when feeling tired No, not just tired. Sleepy, as your eyes are tired and you keep losing track of what people are saying to you.
3. Sleeping from 11:30 P.M. until 2:00
  • A.M., tossing and tuning until 4, then sleeping until 6 gives you eight hours in bed but only four and a half hours of sleep. That’s a huge mismatch that can actually inhibit your sleep drive and cause insomnia all by itself. To prevent that from worsening your sleep issues, when you wake at 2:00A.M., get up and go to read a book in the living room. Being up increases your sleep drive—which just could make you sleepy enough to actually fall asleep when you return to bed. Caution: Don’t stay in bed when you’re awake. A part of your mind will begin to associate the bed with being awake rather than being asleep. And that can turn on a nasty "I’m-not-going-to-sleep!" anxiety that will speed up your engines whenever you get into bed. It’s one of the causes of chronic insomnia.
    4. You need one hour before bed to wind down and get transition from the woman-who-can-do-everything into the woman-who-can-sleep. Unfortunately, most women are not giving themselves one single second. According to the 2007 National Sleep Foundation poll, during the hour before bed, around 60 percent of us do household chores, 37 percent take care of children, 36 percent do activities with other family members, 36 percent are on the Internet, and 21 percent do work related to their jobs.
    5. Staying up late on Friday and Saturday nights and getting up late on Saturday and Sunday mornings is frequently the gift we give ourselves on weekends after a hard week at work. Yet that little gift—small as it is—is enough to screw up our biological clocks. Even if you get to bed early on Sunday night, you will not be ready to sleep, and you will not end up being the happy camper Monday morning.

    Questions 9-13


    ·For questions 9-13, choose from the list A-G which best summarize each part of the article.
    ·For each numberedparagraph (1-5), mark on letter (A-G) on the Answer Sheet.
    ·Do not mark any letter twice.A. Do household chores before bed
  • B. Hit the sheets only when sleepy
  • C. Stay up late only on Saturday nights
  • D. Give yourself an hour before bed
  • E. Wake up at the same time every day
  • F. Beware of Sunday night insomnia
  • G. Get up when awake

Paragraph 3 ______
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