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大多数数青少年需要8.5-9个小时的睡眠 Most teens need about 8? to more than 9 hours of sleep each night. The right amount of sleep is essential for anyone who wants to do well on a test or play sports without tripping over their feet. Unfortunately, though, many teens don't get enough sleep.
Why Aren't Teens Getting Enough Sleep?
Until recently, teens were often given a bad rap for staying up late, oversleeping for school, and falling asleep in class. But recent studies show that adolescent sleep patterns actually differ from those of adults or kids.
These studies show that during the teen years, the body's circadiancircadian rhythm (sort of like an internal biological clock) is temporarily reset, telling a person to fall asleep later and wake up later. This change in the circadian rhythm seems to be due to the fact that the brain hormone melatoninmelatonin is produced later at night for teens than it is for kids and adults. This can make it harder for teens to fall asleep early.
These changes in the body's circadian rhythm coincide with a time when we're busier than ever. For most teens, the pressure to do well in school is more intense than when they were kids, and it's harder to get by without studying hard. And teens also have other time demands — everything from sports and other extracurricular activities to fitting in a part-time job to save money for college.
Early start times in some schools may also play a role in this sleep deficit. Teens who fall asleep after midnight may still have to get up early for school, meaning that they may only squeeze in 6 or 7 hours of sleep a night. A couple hours of missed sleep a night may not seem like a big deal, but can create a noticeable sleep deficit over time.
Why Is Sleep Important?
This sleep deficit impacts everything from a person's ability to pay attention in class to his or her mood. Research shows that more than 20% of high school students fall asleep in class, and experts have been able to tie lost sleep to poorer grades. Lack of sleep also damages teens' ability to do their best in athletics.
Slowed responses and concentration from lack of sleep don't just affect school or sports performance, though. The fact that sleep deprivation slows reaction times can be life threatening for people who drive. The National Highway Safety Traffic Administration estimates that 1,500 people are killed every year in crashes caused by drivers between the ages of 15 and 24 who are simply tired.
(More than half of the people who cause crashes because they fall asleep at the wheel are under the age of 26.)
Lack of sleep has also been linked to emotional troubles, such as feelings of sadness and depression. Sleep helps keep us physically healthy, too, by slowing our body's systems enough to re-energize us after everyday activities. How Do I Know if I'm Getting Enough?
Even if you think you're getting enough sleep, you may not be. Here are some of the signs that you may need more sleep:
difficulty waking up in the morning
inability to concentrate
falling asleep during classes
feelings of moodiness and even depression
How Can I Get More Sleep?
Recently, some researchers, parents, and teachers have suggested that middle- and high-school classes begin later in the morning to accommodate teens' need for more sleep. Some schools have already implemented later start times. You and your friends, parents, and teachers can lobby for later start times at your school, but in the meantime you'll have to make your own adjustments. Here are some things that may help you to sleep better:
Set a regular bedtime. Going to bed at the same time each night signals to your body that it's time to sleep. Waking up at the same time every day can also help establish sleep patterns. So try to stick to your sleep schedule even on
weekends. Don't go to sleep more than an hour later or wake up more than 2 to 3 hours later than you do during the week.
Exercise regularly. Try not to exercise right before bed, though, as it can rev you up and make it harder to fall asleep. Many sleep experts believe that exercising 5 or 6 hours before bedtime (in late afternoon) may actually help a person sleep.
Avoid stimulants. Don't drink beverages with caffeine, such as soda and coffee, after 4 PM. Nicotine is also a stimulant, so quitting smoking may help you sleep better. And drinking alcohol in the evening can also cause a person to be restless and wake up during the night.
Relax your mind. Avoid violent, scary, or action movies or television shows right before bed — anything that might set your mind and heart racing. Reading books with involved or active plots may also keep you from falling or staying asleep.
Unwind by keeping the lights low. Light signals the brain that it's time to wake up. Staying away from bright lights (including computer screens!), as well as meditating or listening to soothing music, can help your body relax.
Don't nap too much. Naps of more than 30 minutes during the day may keep you from falling asleep later.
Avoid all-nighters. Don't wait until the night before a big test to study. Cutting back on sleep the night before a test may mean you perform worse than you would if you'd studied less but got more sleep.
Create the right sleeping environment. Studies show that people sleep best in a dark room that is slightly on the cool side. Close your blinds or curtains (and make sure they're heavy enough to block out light) and turn down the
thermostat in your room (pile on extra blankets or wear PJs if you're cold). Lots of noise can be a sleep turnoff, too.
Wake up with bright light. Bright light in the morning signals to your body that it's time to get going.
If you're drowsy, it's hard to look and feel your best. Schedule "sleep" as an item on your agenda to help you stay creative and healthy.
There are many wetlands（湿地） in China and some of them have become the world's important wetlands. The Chinese Yellow Sea Wetlands are among them. They are in Yancheng，Jiangsu Province. They are home for many different kinds of birds and animals. The world's largest Milu Deer Nature Reserve（自然保护区） is in them. More than 700 milu deer live freely there. There are not many red-crowned cranes in the world， but every winter you can see some in the Red-crowned Cranes Nature Reserve in the Yellow Sea Wetlands.
The temperature in the wetlands is usually neither too high nor too low. There is a lot of rain and sunshine, too. They are really good places for wildlife（野生生物）。 Offering food and home for some special kinds of animals and birds is not the only reason why we need to protect wetlands. Wetlands are important because they also prevent flood. But some people want to change the wetlands to make more space for farms and buildings. This means there will be less and less space for wildlife.
Luckily, more and more people are beginning to realize the importance of wetlands and wildlife. Every year, on February 2nd, many activities are held to tell people more about wetlands.
21. The Chinese Yellow Sea Wetlands are in the _______ of China.
A. south B. west C. east D. north
22. Usually the weather in the wetlands is _______.
A. hot B. cold C. pleasant D. dry
23. The World Wetlands Day is on _______.
A. February 2 B. April 22 C. June 25 D. March 22
24. We must protect wetlands because _______.
A. they are home for wildlife
B. they can prevent flood
C. they can offer food to the animals and birds
D. all of the above
Rules for the University Entrance Examination in America
●You must be at the examination center ten minutes before the examination starts. If you are more than ten minutes late, you may not enter the examination center. The examination takes place at the same time in different states.most,teens,need,about,8.5,to,more,than。
●You must have proof of your name and grade as well as official examination number. Show these when you come to the examination center.
●Depending on which examination you are taking, you may bring certain items into the examination center. Mathematics examinations may allow you to use electronic calculators (计算器). Other subjects may allow you to use dictionaries and other reference material. Please read the notes sent with your timetable carefully.
●You must bring your own pencils. None will be provided for you. The following items are not allowed in the examination center: Walkman(随身听) and radios, head sets, any food or drink, schoolbags, electronic equipment (unless specifically permitted for various subjects), and mobile phones.
●Once in the center, you must sit at the desk with your examination number on it. When you sit down, place your examination number at the top of your desk.
●You must remain silent during the examination. You must not disturb other people who are taking the test.
●If you need a drink or toilet break, you should raise your hand and wait for the supervisor (监督者) to speak to you. You will be given water or the supervisor will take you to the bathroom. You are not allowed to talk with anyone during the break.
●You must write your answers in the official answer sheet. Your supervisor will provide extra paper if you wish to make notes.
●You may leave the examination room at any time if you do not plan to return. If you finish early and want to leave, please move well away from the examination center.
●The supervisor will warn you fifteen minutes, five minutes and one minute before the end of the examination. When the supervisor says that the time is up, you must put down your pencil and wait at your desk until your paper is collected.
25. What are you allowed to have with you when you take mathematics
A. Related material. B. A cell phone.
C. Proof of yourself D. A dictionary.
26. What should you do if you finish the test early and want to get a better result?
A. Leave the room immediately.
B. Remain in your seat and check again.
C. Raise your hand to inform your teacher.
D. Take some notes carefully.
27. What can be provided for you during the exam?
A. Pencils. B. Food and drink. C. Calculators. D. Extra paper
I. Listening Comprehension
Part A. Short Conversations
Directions: In part A, you will hear ten short conversations between two speakers. At the end of each conversation, a question will be asked about what was said. The conversations and the questions will be spoken only once. After you hear a conversation and the question about it, read the four possible answers on your paper, and decide which one is the best answer to the question you have heard.
1. A. In a restaurant B. On a train
C. At a bus stop D. At the airport
2. A. At home B. At a bar
C. At a concert D. with some friends
3. A. Teacher and student B. Boss and secretary
C. Patient and doctor D. Shop assistant and customer
4. A. $1.40 B. $6.40 C. $4.30 D. $8.60
5. A. She is going away. B. She won’t give up her job.
C. She will be sorry to leave. D. She will not buy him a present.
6. A. The man shows the disappointment at what the woman will do.
B. The man would like to join them.
C. The man suggests the woman should reconsider her plan.
D. The man tries to persuade the woman not to go with Jerry.
7. A. The modern art prints are too expensive.
B. He really appreciates the woman’s gift.
C. He hopes the woman likes modern art.
D. People who enjoy modern art would like the prints.
8. A. He hasn’t had time to try it on yet.
B. It doesn’t fit him very well.
C. He needs a green shirt to have a change.
D. He’s not sure whether he likes the pattern.
9. A. The man can’t come for the appointment at 3:15.
B. The man wants to change the date of the appointment.
C. The man is glad he can get in touch with the doctor.
D. The man was confused about the date of the appointment.
10. A. Internet surfing B. Stock exchanging
C. Mountain climbing D. Job hunting
Section B Passagesmost,teens,need,about,8.5,to,more,than。
Directions: In Section B, you will hear two short passages, and you will be asked three questions on each of the passages. The passages will be read twice, but the questions will be spoken only once. When you hear a question, read the four possible answers on your paper and decide which one would be the best answer to the question you have heard.
Questions 11 through 13 are based on the following passage.
11. A. On Highway 22 B. On Highway 60
C. On Highway 109 D. On Highway 119
12. A. She was driving too fast.
B. She was not driving at a required speed.
C. She had too many people in the car.