Tom and Mike are good friends. They are good to kids. They want to find summer jobs. One day Tom tells Mike that Beidaihe Kids Summer Camp needs help with sports, music and computers. They are both very glad to hear this.

    Tom can play basketball and volleyball, and he can swim, too. Mike can play the violin, the drums and the guitar, and he also likes soccer. Tom and Mike like computers very much. Can they join the Summer Camp?

    Many people know that rubbish is a big problem on planet Earth. What many people don't know is that junk (垃圾) has become a problem in outer space too.

    According to BBC News, there are more than 22, 000 pieces of space junk floating around the earth. And these are just the things that we can see from the surface of the earth by telescopes (望远镜). There are also millions of smaller pieces of junk that we can't see.

    Objects, like bits of old space rockets or satellites, move around the planet at very high speeds, so fast that even a very small piece can break important satellites or become dangerous to astronauts. If the tiniest piece of junk crashed into a spaceship, it could damage the vehicle.

    To make things worse, when two objects in space crash, they break into many smaller pieces. For example, when a U. S. satellite hit an old Russian rocket in 2009, it broke into more than 2,000 pieces, increasing the amount of space junk.

    To reduce additional space junk, countries have agreed that all new space tools can only stay in space for 25 years at most. Each tool must be built to fall safely into the earth's atmosphere after that time. In the upper parts of the atmosphere, it will burn up.

    Many scientists are also suggesting different ways to clean up space junk. In England scientists are testing a metal net that can be fired into space junk. The net catches the junk and then pulls it into the earth's atmosphere to burn up. The Germans are building robots that can collect pieces of space junk and bring them back to Earth to be safely destroyed.

    "The problem is becoming more challenging because we're sending more objects into space to help people use their mobile phones and computers," says Marco Castronuovo, an Italian space researcher.

    "The time to act is now. The longer we leave the problem, the bigger it will become," he says.

    Started in 1636, Harvard University is the oldest of all the colleges and universities in the United States. {#blank#}1{#/blank#}

    In the early years, these schools were much alike. Only young men went to college. {#blank#}2{#/blank#} Little was known about science then, and one kind of school could teach everything that was known about the world. When the students graduated, most of them became ministers or teachers.

    In 1782, Harvard started a medical school for young men who wanted to become doctors. Later, lawyers could receive their training in Harvard's law school. {#blank#}3{#/blank#} Soon it began teaching American history.

    As knowledge increased, Harvard and other colleges began to teach many new subjects. {#blank#}4{#/blank#}

    Today, there are many different kinds of colleges and universities. {#blank#}5{#/blank#} There's so much to learn that one kind of school can't offer it all.

A. In 1825. besides Latin and Greek, Harvard began teaching modern languages, such as French and German.

B. Most of them are made up of smaller schools

C. Yale, Princeton and Columbia were opened soon after Harvard

D Students were allowed to choose the subjects that interested them

E. All the students studied the same subjects, and everyone learned Latin, Greek and Hebrew

    There are some skills for students to listen to the teachers in class, which means you're going to have to practice them. Just as you would have to practice basketball to be a better player, you also have to practice listening. How to listen in school? {#blank#}1{#/blank#}

    One of the things you'll need to do is to make sure that your mind doesn't wander(漫游). It's easy to start thinking about other things, especially when you are not interested in the subject. {#blank#}2{#/blank#}

   Next, listen for the main ideas. If you want to catch every little piece of information, you'll feel tired and bored. {#blank#}3{#/blank#} Not only does this show respect to the teacher, it also helps prevent your mind from wandering. {#blank#}4{#/blank#}Or it could just be someone talking to their neighbors who shouldn't be, it can even be some birds outside the classroom window, or a group of kids who are talking loudly as they pass the door to your room.

    Finally, you need to take notes because you will not remember everything the teacher said. You'll have to take down the notes so that you can study it after class. {#blank#}5{#/blank#}

    Listening isn't always easy, but if you follow these simple steps, you'll be much more successful in your classes.