When you watch 3D movies or TV, you have to wear a special pair of glasses. The 3D glasses make the images from the screen look like they are there in the room with you.

    Three-dimensional, or 3D, means having three dimensions（维度）: width, height and depth. 3D technology（技术） is based on the way the human brain（大脑） and eyes work. Because the pupils of a person's eyes are about 6.5era apart（分开）, when we look at something, each eye sees,it from a different angle（角度）. Our eyes send the two images to our brain, and the brain puts them together. The small difference between the image from the right eye and the image from the left eye allows us to see depth.

    When we view pictures and television in two dimensions, each eye gets the same information. That is because the image has no real depth, and there is only one of viewing it. So the goal of 3D technology is to get a different image into each of the viewer. It uses two film projectors. One projects a left eye image and the other projects a right image. The 3D glasses allow us to see a different image in each eye.

    While watching 3D films, we feel that we are in the same environment as the things we're watching. However, it also has its disadvantages. The 3D glasseswork by controlling the amount of light that reaches the eyes. It makes the screen look darker. What's more, people with eye problems may get headaches if they spend too much time watching 3D movies，because their brains need to work harder to "read" the images.

    In life, everyone once struggles for a dream, whether it's successful or not. I still clearly remember one day when I was in high school. I saw on a website that China's. Got Talent's mass-election（海选）for the best singers was going on. I was very excited and decided to go and try out. But it wasn't as easy as I had thought. When I got there, I saw at least 100 people already waiting in line. My hands started to sweat and shake as my turn got close. I got up and started singing, but I sang so badly that I stopped before I even finished the song. Afterwards I quickly said goodbye to my friends and walked home crying. I thought that I would never be able to show my face in public again.
    However, after about a year, that terrible experience became a funny memory. I realized that I didn't need to care about losing that dream, because I made a new and more realistic one. I'm good at English, as well as other subjects. I made it my goal to get accepted into Columbia University. Columbia is hard to get into, and about 1,300 students from all over the world are accepted every year. Though it is hard to get into, I think my dream will come true someday by working hard.

    Dianna was born in a rich family on July 1st,1961. On July 29, 1981, Diana married Prince Charles. Later she gave birth to Prince William and Prince Harry.

    Dianna enjoyed taking part in  international Charities（国际的慈善机构）. One day in July 1991, she went to a hospital to see AIDS patients with Barbara Bush, the wife of the president of the United States at the time. Princess Diana talked to an AIDS patient who was unable to stand up. She even hugged(拥抱) him and encouraged him to fight against the illness(疾病). The patient was very grateful and said, “AIDS patients do need warm hugs.” Of course, she made it. Unfortunately, she died in August 1997. British Prime Minister, Tony Blair said in his speech that Diana was the People's Princess.

    After her death, people set up a fund(基金)to remember Diana and help those who need help.

    Several months ago, my husband and I were on an island for a long weekend with our five-year-old twin daughters. As we went back and talked about what to do next, our girls jumped in and told us exactly what they wanted to do. "We want to go to the butterfly museum," said Emily and Hanna.

    As soon as we walked into the main area of the museum, we saw thousands of beautiful butterflies. They all flapped (拍打) their colourful wings.

    My girls were jumping up and down, and I knew it was right for us to take them to the museum. They were having so much fun.

    I turned to our museum tour guide because I was curious (好奇的) and asked, "How long do butterflies live?"

    She said, "About ten days."

    "What can butterflies do in ten days?" I asked.

    The guide stopped, looked at me, and said, "They make the world a more beautiful place."

    "Wow," I said, "I never thought about butterflies like that. Thank you."

    After we said goodbye, I couldn't stop thinking about what the guide had said. She was right. We all have something to give the world with the time we have. When we put our gifts on taking care of each other every day, we can make a difference.

    Appreciate (欣赏) the impact (影响) you can have on your family, friends, co-workers and neighbours. Like a butterfly, you have your own way of making the world more beautiful for everyone.

    A long time ago, there was a king who liked music so much that he ordered his men to get him the best instrument in the world.

    One day, a young man offered the king a harp (竖琴). The king took it to the palace, but when he started playing it, the harp was out of tune.

    Many other musicians tried it, and they agreed that the harp was useless(没用的) and the king had been cheated. The harp was thrown out as rubbish.

    A poor little girl later found the harp. And even though she did not know how to play, she decided to have a try. She played and played, for months and years, always with the harp out of tune, but she played better and better.

    Then one day, suddenly, the harp began to play the most beautiful music. It was a magic harp, and could only be played well by someone willing to spend much time practicing.

    One day, the king heard the music from his window, and the girl was invited to the palace. When the king saw the girl playing the harp, he was full of joy. At that moment he made the girl his private musician, giving her and her family lots of money.