Kumar and his two friends built a robot and named it Athena. They would go for Battle of the Bots--the city's biggest robot competition, and it would start in two days. The winning team would get $5,000.

     "How are we going to beat (打败) the Cougars?" asked Alex. The Cougars was the team that won the last two years' competitions.

    Kumar said, "The Cougars always build a big and strong (强壮的) robot. But usually their robot isn't very fast."

    "Our robot is fast," Alyssa said.

    "Yes!" Kumar said. "Don't worry. I have a plan for how to do it." Kumar told the group his plan and they began to work.

    Two days later, the competition began. Kumar said to his friends, "I' m sure the plan will work and Athena will win. Just wait and see."

    Athena won all of her first battles (较量). The Cougars' big, strong robot, The Avenger, did well, too. By the end of the day, The Avenger and Athena were the only two robots left in the competition.

    Soon the battle between Athena and the Avenger began. The Avenger lunged (猛扑) for Athena, but the small robot was too quick for him. Athena went behind The Avenger and, before the larger robot had time to turn, Athena hit (攻击) him from behind. The Avenger fell" down and couldn't move.

    The three friends all jumped up excitedly. "Now it's time for the real question," said Alex“      ”

    On May 17, 2009, according to the plan, Mike Good and I would take a space walk to the Hubble Space Telescope to repair an instrument. The power supply on this instrument had failed, so it could no longer be used. I would be the person doing the repair and Mike my assistant.

    Working in space is more difficult than you can imagine. As there is no gravity, you can't stand and any slight push can result in tragedy -you can be pushed into space, never be back.

    We got to the telescope. Before we could replace the power supply, we would have to remove from the telescope a handrail fixed with four screws. Having taken out the first three, I found the fourth stripped. I realized that the handrail would not come off, which meant we could no longer be able to replace the power supply and repair that instrument, which meant scientists could no longer look at the universe and find life on other planets.

    I tried all kinds of things, and nothing worked. Then Houston, the control centre on the earth, called up and told me to use the tape to tape the bottom of the handrail and pull it off the telescope. They said it was going to take about 27 kilograms of force for me to do that.

    I knew what it meant: The handrail could be completely pulled off and the safety tether might break, and I might therefore be pushed into space.

    Mike was next to me in his space suit but he could not take over my role. I turned and looked into the cabin where my five crewmates were, and nobody in there had a space suit on. However, I knew they were all looking at me. "Come on Mass, we are all behind you." The telescope must be repaired.

    "Bam!" The handrail came right off. The rest of the walk went well. We finally got the new power supply in. They tried it; turned it on from the ground. The instrument came back to life.

    At the edge of darkness, after about eight hours, I turned around and saw the Earth from our altitude at Hubble, 568 kilometers up. I saw the huge round pure blue globe home planet. It's the most beautiful, magnificent thing I've ever seen. It's like looking into heaven. It's paradise.

    If music makes you smarter and exercise helps you to think, surely exercising to music can turn you into an intelligent(聪明的) person.

    A team of scientists from Ohio State University did tests on 33 volunteers who were getting better from heart problems following operation(手术). They found that people who exercised while listening to "The Four Seasons" did much better on language ability tests than without music.

    "Facts suggest that exercise improve the learning ability of people with heart problems," said the scientist Charles Emery, who led the study. "And listening to music is thought to enhance understanding. We just wanted to put the two results together." he added.

    The volunteers said they felt better after exercising with or without the music. But their improvement on the test doubled after listening to music during exercise. Scientists have shown it is true that music can be good for health. It helps cut down stress, sadness and nervousness. And it also wakes up the body and improves memory and thoughts.

    In medical fields, music is used widely for patients who have had headaches before and after operation. "The Four Seasons" was used because of its soft tempo(节拍) and better results in earlier research.

    "Exercise seems to cause better changes in the nervous system and these changes may have a direct result on learning ability." Emery said. Scientists have been studying the result of music on understanding since the early 1950s. By 1990, scientists were using Mozart's music to help children with speech disorders. Mozart was chosen because his music is not overexciting. A study showed students who listened to Mozart scored higher marks in an intelligence test. With important exams coming, your parents will not probably allow you to listen to music. But perhaps now you have good reasons to argue with them.

    We all know that many inventions have changed our life a lot. They play important roles in our daily life. Here are some interesting inventions.