On May 23, 1989, Stefania Follini came out from a cave at Carlsbad, New Mexico. She hadn't seen the sun for eighteen and a half weeks. Stefania was in a research program, and the scientists in the program were studying body rhythms. In this experiment Stefania had spent 130days in a cave, 30 feet in depth.

    During her time in the cave, Stefania had been completely alone except for two white mice. Her living place had been very comfortable, but there had been nothing to tell her the time. She'd had no clocks or watches, no television or radio. There had been no natural light and the temperature had always been kept at 21℃.

    The results were very interesting. Stefania had been in the cave for over four months, but she thought she had been there for only two. Her body clock had changed. She hadn't kept to a 24-hour day, she had stayed awake for 20～25 hours and then had slept for 10 hours. She had eaten fewer meals and had lost 171bs in weight as a result! She had also become rather depressed.

    How had she spent her time in the cave? As part of the experiment she'd done some physical and mental tests. She'd recorded her daily activities and the results of the tests on a computer. This computer had been specially programmed for the project. Whenever she was free, she'd played cards, read books and listened to music. She'd also learned French from tapes.

    The experiment showed that our body clocks are affected by light and temperature. For example， the pattern of day and night makes us wake up and go to sleep. However, people are affected in different ways. Some people wake up naturally at 5:00 a.m., but others don't start to wake up till 9:00 or 10:00 a.m. This affects the whole daily rhythm. As a result the early risers are at their best in the late morning. The late risers, on the other hand, are tired during the day and only come to life in the afternoon or evening!

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Top 5 Must See Places in Beijing

    Beijing is an old capital city with a lot of tourists attractions. What is the most representative place in Beijing? The answers are various. Here are the Top 5 Must See Places in Beijing.

1）. Forbidden City

    The Forbidden City is the ideal place for you to begin your exploration of Beijing. Make sure to wear comfortable shoes as you have to walk a lot! A multilingual guide recorder is recommended, as it can tell you the stories behind the palace.

Opening Hour: 8:30-17:00

Entrance Fee: RMB 60

2）. Tian'anmen Square

    Lying in the heart of Beijing City, it is the place for massive parades and gathering. It boasts of the largest square of such kind in the world. At sunrise and sunset the raising and lowering ceremony of the Chinese National Flag is well worth seeing.

Ticket fees: Free

Opening Time: Whole Day

3）. Great Wall

    Most of the sections of the Great Wall in Beijing are well-preserved, and the most famous section is Badaling. For the Great Wall hiking, get ready for strong footwear. For hot weather, please also prepare sunblock, sunglasses and water.

Badaling Great Wall:

Ticket Fees: RMB40 (Nov. 01 to Mar. 31); RMB 45 (Apr. 01 to Oct. 31)

Open Hours: 6:40 to 18:30

4）. Summer Palace

    Regarded as the largest imperial garden in China, the Summer Palace is in fact a park-styled royal retreat. With masterly design and artistic architecture integrating the highlight of Chinese garden arts, it has earned a title of "Royal Garden Museum".

Open Time: 6:30-20:30

Ticket Fee: RMB 40 (low season) / RMB 50 (peak season during the holidays)

5）. Temple of Heaven

    The Temple of Heaven worked as sacrificial compound buildings for the Ming and Qing emperors. What's the intriguing by-production of the temple is that if you enter the Temple of Heaven in the early morning, you can find many people doing all types of Kungfu, Taiji, dancing and other morning exercises.

Open Time: 6:00-21:00

Ticket Fee: RMB 35

    With the development of modern science and technology, the functions of cellphones have changed greatly. {#blank#}1{#/blank#}The only difference may be that they fit in your pocket and you pay by the minute to use them. Some of the things a cellphone can do for you will be available this year:

Surf at speed

    Cellphones that let you use the Web have been around for years. So, what's new? Well ,  faster third-generation (3G)  networks that let you surf at anywhere. {#blank#}2{#/blank#}Possible choices are from IJG Electronics VX 8000 and Motorola V1150.Listen as you go.

    {#blank#}3{#/blank#} There is no doubt that it is about to change. Sony Ericsson's new W8001 can hold around 150 songs in its 500 MB memory. And Samsung's SPH-V5400 even comes with a l. 5 GB hard drive. Mobile phones may eventually replace miniMP3 players, especially for teens. Say cheese.

    Camera cellphones are not new either but most of them have limitations: around l- megapixel  (百万像素 ) .  However new technology has made 2-megapixel units more common ,and 3-megapixel units are showing up soon. Some 2-megapixel models, like Sony Ericsson's K7501, offer limited zoom and focus controls.   {#blank#}4{#/blank#}Portable TV.

    You say you like "watching TV"? That's what Samsung MMA700 wants to give you. The new model lets users watch popular TV programmes~ for a fee. Other choices are Nokia's 6620, Sanyo's MM740 and NEC's N940. {#blank#}5{#/blank#}

    The above are just a handful of what you ' ll see in the coming months.  Further down the road, your mobile phone may play a host of other roles, such as mobile credit card, position locator and so on. So what is there that a cellphone can't do?

A. The NEC model lets you watch public TV - no fee.

B. Without a cellphone, you can do nothing in your daily life.

C. Nowadays, new cellphones are much cheaper than old ones.

D. Today's do-it-all mobiles have a lot in common with the computer.

E. This then allows a carrier to send video, music, and games to your phone.

F. Others, like LG's recent A7110, can even capture 30 minutes of full-motion video.

G. The problem with most cellphone MP3 players is that they hold only a handful of songs.

    In my generation, most people assume. We assume that after getting a driver's license, we should see a brand new car sitting in our driveway. We assume that the latest iPhone product should be in our hands as soon as something goes wrong with our old one. We also assume that college, being as expensive as it is, is given. However, what we don't realize is that all of these things are very special privileges.

    New cars, the latest technology and college fees are something that most people have in the place where I live. I'm not necessarily complaining about this. I live in a very fortunate area, and I try to remind myself of that every day.

    Getting nice things is great, but sometimes, the competition that rules our lives gets too fierce. When someone else gets something great, you begin to think, "Why can't I have that?" When everyone around you goes to college, you think that one day you will obviously do the same, because who doesn't?

    Even now, being almost done with my first year of college, I constantly see people who forget why we're here, and how lucky we are to be on this campus. All of the distractions can surely keep you from doing your best, and they can easily make you forget your real purpose at college. The parties, friends, events, and overall social life can move you into a never-ending whirlpool (旋涡）of not doing schoolwork. Having fun is a part of life, but balance is the key when it comes to college.

    Appreciation nowadays is slowly fading into a distant thought. We constantly forget how lucky we are to have the things and the life that we do. Surely, who doesn't dream of a new car waiting for them, or that brand new iPhone that you see in all of the commercials? But wanting something is different from expecting it. Setting yourself up with an "I should get this" attitude will only push appreciation further away.

    Appreciate what you have, but don't expect what you don't have. Say thank you to those who help and support you, and realize that whoever you are, you're lucky in a great way.

    If you live in Shanghai, Beijing or many other cities, you may see many orange bicycles on the streets these days.

    These bikes are owned by a company called Mobike. You can order a bike through an app on your phone. When you find a bike, you just scan a QR code （扫描二维码） on the bike so you can use it. You don't need to return the bike to a station- you can park it anywhere.

    China was known as "the kingdom of bicycles" about 30 years ago. But more people choose to drive cars and catch the subway these days. Bike rental（租凭的） services like Mobike are bringing bikes back.

    "Back then, I got the feeling that Chinese people were trying to be modern and push away the past. So they did not want to be linked with bicycles," said Ines Brunn, a German woman who runs a bike store in Beijing. "I do believe changes in people's tastes will shape new thinking about bikes."

    Online rental services are making biking more convenient, but it's still not easy to ride bikes in Chinese cities. Cars often take up bicycle lanes （道路）. Bikers have to ride next to cars in car lanes, which can be very dangerous.

    Beijing plans to build over 3,200km of new bike lanes. Drivers who drive in bike lanes will be punished. Traffic signs will be put up to better protect bikers.