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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    It's not easy being a teenager（13 years old ~19 years old）—nor is it easy being the parent of a teenager. You can make your child feel angry, hurt, or misunderstood by what you say without realizing it yourself. It is important to give your child the space he needs to grow while gently letting him know that you you'll still be there for him when he needs you.

    Expect a lot from your child, just not everything. Except for health and safety problems, such as drug use or careless driving; consider everything else open to discussion. If your child is unwilling to discuss something, don't insist he tell you what's on his mind. The more you insist, the more likely that he'll clam up. Instead, let him attempt to solve things by himself. At the same time, remind him that you're always there for him should he seek advice or help. Show respect for your teenager's privacy. Never read him his mail or listen in on personal conversions.

    Teach your teenager that the family phone is for the whole family. If your child talks on the family's telephone for too long, tell him he can talk for15 minutes, but then he must stay off the phone for at least an equal period of time. This not only frees up the line so that other family members can make and receive calls, but teaches your teenager moderation（节制）. Or if you are open to the idea, allow your teenager his own phone that he pays for with his own pocket money or a part –time job.

    What do you do for fun in your spare time? Do you like reading? Do you often go to a book store? There is a store that is so different from others.

    The World's Smallest Bookstore, whose official name is just these three words, sits quietly about 100 miles northeast of Toronto.

    The bookstore is about 10 feet by 10 feet, so it is easy to imagine how tiny it really is. The bookstore is open 24 hours a day. Inside the bookstore are various books, especially literary books and classic authors' works. So if you are looking for something less popular, you may get a bit disappointed there.

    Another special feature of this bookstore is that each book only costs three dollars. All the expenses are paid on the honor system, which means buyers should make a note of what they've bought and leave their money by themselves. So the tools of the trade in this bookstore are quite simple: pens, papers, light bulbs and a label-maker.

    In order to catch passers-by's attention, the billboards (广告牌) of the bookstore are several times bigger than the store itself. With these large eye-catchers, many people are willing to stop by and have a visit.

    Earthquakes are something that people fear. There are some places that have few or no earthquakes. Most places in the world, however, have them regularly. Countries that have a lot of earthquakes are usually quite mountainous.

    The most talked about earthquake in the United States was in San Francisco in 1906. Over 700 people died in it. The strongest one in North America was in 1964. It happened in Alaska.

    Strong earthquakes are not always the ones that kill the most people. In 1755, one of the strongest earthquakes ever recorded was felt in Portugal. Around 2,000 people died.

    In 1923, a very strong earthquake hit Tokyo, Yokohama area of Japan. A hundred and forty thousand people died. Most of them died in fires which followed the earthquake.

    One of the worst earthquakes ever was in China in 2008. It killed a large number of people. The worst earthquake ever reported was also in China, in which 400,000 people were killed or injured. This earthquake happened in 1556.

    Earthquakes worry people a lot. The reason is that we often do not know when they are coming. People cannot prepare for earthquakes.

    My wife, daughter, and I moved into our home nine years ago and we spent a lot of time and energy in the yard to get it looking like the way it does today. We live on a corner, higher than street level, and the entire side of the yard is surrounded by a professionally built rock wall. The front of the house though is another story because instead of a wall along the sidewalk, the rocks appear to be just thrown up onto the dirt as if someone were in a hurry to finish.

    We did the best we could with what we had to work with and called this area our "rock garden". Whenever we had leftover flowers or plants, Denise or I would stick them out front, just to bring some color to the area. We would do all of the yard work on our own, even the tiring weed-pulling.

    Last summer I had reached the end of the rock garden and found a tiny little plant that I could not immediately identify, I knew I didn't plant it and Denise claimed that she didn't either. We decided to let it continue growing until we could figure out what it was.

    Weeks passed and as I made my way back to the mystery plant, it appeared to be a Sunflower with a tall skinny stalk（茎，杆）and only one head on it. I decided to baby it along and weed around it. As I pulled rocks from the area to get to the weeds, I noticed something unusual. The Sunflower had not started where I saw the stalk begin. It actually had begun under a big rock and grown under and around it to reach the sun.

    That's when I realized that if a tiny little Sunflower didn't let a big rock stand in its way of developing, we too have the ability of doing the same thing. Once our environment begins to see that we believe in ourselves like that little Sunflower, we can attain the same nourishment（营养）and growth as well.

    Stand tall like the Sunflower and be proud of who and what you are and the environment will begin to support you. You will find a way to go under or around your big obstacle in order to reach your desires.

    There are plenty of mindless activities to keep a child busy in this information age. Yet despite the competition, my 8-year-old daughter Alice wants to spend her leisure time writing short stories. She wants to enter one of her stories into a writing contest, a competition which she won last year.

    As a writer, I know about winning contests—and about losing them. I know what it is like to work hard on a story only to receive a rejection letter from the publisher. I also know the pressure of trying to live up to a reputation created by previous victories. What if she doesn't win the contest again? That's the strange thing about being a parent. So many of our own past scars and destroyed hopes can resurface in our children.

    A revelation (启示) came last week when I asked her, "Don't you want to win again?" "No," she replied. "I just want to tell the story of an angel going to first grade."

    I had just spent weeks correcting her stories as she spontaneously (自发地) told them. Telling myself that I was an experienced writer guiding the young writer across the hall, I offered suggestions for characters, conflicts and endings for her tales. The story about a fearful angel starting first grade was quickly "guided" by me into the tale of a little girl with a wild imagination taking her first music lesson. I had turned her contest into my contest without even realizing it.

    Staying back and giving kids space to grow is not as easy as it looks. Because I know very little about farm animals who use tools or angels who go to first grade, I had to accept the fact that I was co-opting (借鉴) my daughter's experience.

    While stepping back was difficult for me, it was certainly a good first step that I will quickly follow with more steps, putting myself far enough away to give her room but close enough to help if asked. All the while I will be reminding myself that children need room to experiment, grow and find their own voices.