In the early 1990s the word "Internet" was strange to most people. But today, Internet has become a useful tool for people all over the world. Maybe Internet has been the greatest invention in the field of communication in the history of mankind. Communicating with others on the Internet is much faster. We can chat with a person who is sitting in the other part of the world. We can e-mail our friends and they can read the e-mails within a minute.
   Giving all kinds of information is probably the biggest advantage of the Internet. We can use search engines to find the information we need. Just type in a keyword or keywords and the search engine will give us a list of suitable websites to look at.

   We can enjoy a lot on the Internet by downloading games, visiting chat rooms or surfing(浏览)websites. There are some games for free. We can meet new and interesting people in the chat now. We can also listen to music and see films.
   Now, there is a lot of service on the Internet such as online banking, job finding and ticket buying. We can also do shopping and find nearly all kinds of goods. Sometimes we can find something that is quite good but very cheap.

      It is said that people born on different dates have different characteristics. For example, people who were born between March 21 and April 20 are likely to be active and strong. They like power and enjoy adventures.
     People who were born between April 21 and May 21 are likely to learn more slowly, But they can remember what they learn well. They love children and usually have many friends.
     People who were born between May 22 and June 21 are bright and humorous. They like to talk and enjoy wearing fine clothes.
     People who were born between June 22 and July 22 think deeply. They would rather hide their feelings than express them.
     People who were born between July 23 and August 22 are interested in many subjects and it is interesting to hear them talk.
     People who were born between August 23 and September 22 are said to be calm and thoughtful. They like to read and often become successful scientists.
    If you have free time, you can read about star signs to see if your characteristics match your birth date.

Dreams may be more important than sleep. Some people don't need much sleep. But we all need to dream, scientists say.

    Dreams take up about one quarter of our sleeping time. People have several dreams each night. Dreams are like short films. They are usually in color. Some dreams are like old films. They come to us over and over again. That may be because the dreamer is worrying about something. Dreaming may be a way of trying to find an answer.

    Some people get new ideas about their work from dreams. They could have been thinking about their work all day. These thoughts can carry over into dream. Sometimes we wake up with a good feeling from a dream. But often we can't remember the dream.

    Dreams can disappear quickly from memory. Too much dreaming can be harmful. The more we sleep, the longer we dream. The mind is hard at working when we dream. That is why we may have a long sleep and still wake up tired.

    Height is just one of the thousands of features your genes decide. In fact, because you have two parents, your genes provide you a height that usually lands somewhere between the height of each parent. If both your parents are tall, then most probably you will be tall, too, but if you have questions about how tall you're going to be, ask your doctor if he or she can help you find it out.

    But genes don't decide everything. For example, eating an unhealthy diet can keep you from growing to your full potential(潜力). Getting plenty of sleep and enough exercise will help you grow to the expected height.

    No doubt you're wondering how fast you should grow. It depends. There's no perfect or right answer. Generally speaking, kids grow about 2 inches (6 centimeters) a year between age 3 and the time when they start puberty (when your body starts changing and becoming more grown up).

    Your doctor will know how your growth has been going over the years. Two centimeters here and 2 inches there are not nearly as important as the height you're at now, how you've been growing up to this point, and what other changes your body may be going through.

    Don't be scared if you seem to have grown a lot in a very short time. Everyone has a growth spurt（高峰）during____The age for starting puberty is about 10 for girls and about 11 for boys. But it can be earlier or later —between 7 and 13 for girls and 9 and 15 for boys.

    You'll usually begin to notice that you're growing faster about a year or so after your body starts to show the first changes of puberty.

    From a plane we can see the fields, cities, mountains or seas below. If we go into space, we see more and more of the Earth. People and man-made satellites have been sent out into space to observe the Earth carefully and people have learnt mire about the Earth in the last few years.

    The sea looks very beautiful when the Sun is shining on it. But it can be very terrible when there is a strong wind.

    The sea is very huge. It nearly covers three quarters of the Earth. The sea is also very deep in some places. There is one place where the sea is about 11 kilometers in depth. The highest mountain is the world is about 9 kilometers high. If that mountain was put into the sea at that place, there would be still 2 kilometers of water above it!

    In most parts of the sea, there are many kinds of fishes and plants. Some live near the top of the sea. Others live deep down. There are also a lot of small living things, and quantities of fishes live by eating them.

    The sea can be very cold. When people go down, the sea becomes colder and colder. Only some men could go down into the deep sea at first. But in 1970, five women scientists lived in the deep sea for fourteen days.