Last year, a special kind of glove came out. It was invented to help bind people to learn Braille,which is a special system for the blind to read by touching. Shaking motors (震动马达) are put on each finger of the glove. They can make different sounds to tell a user which letter he is touching.Recently, two British college students have invented another special glove for the blind. It can make the user feel small and quick movements. An ultrasonic sensor(超声波传感器)with a battery is put on the back of the glove. When the user wearing the glove is close to an object（物体）, ultrasonic waves( 超声波)from the glove are sent out  (发出). As soon as they hit the object in front,  the waves will return to the glove. Then the waves cause the glove to shake. And the ultrasonic sensor makes different kinds of sounds. The sounds make the user know how far he is from the object.

  In the college invention competition, the two students got first prize and won 1,540 pounds. One of the designers said, "Now the ultrasonic sensor on the glove is quite large. We're going to use the money to develop a smaller and lighter ultrasonic sensor.

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Americans love to drive. They have drive- in movie theaters and drive- through restaurants. And they also drive for vacations. They often call it the "Great American Road Trip": the whole family gets into a car or recreational vehicle(RV,旅行房车), and goes on a summertime trip across the country.

American cars are always big, but RVs are the biggest. These are houses on wheels. RVs have kitchens, bathrooms and bedrooms. All across the country you can find RV parks. They are places to park your RV and spend the night. And, if you can't find a good park, you can always make your home in a grocery store parking lot(杂货铺停车场).

When your little brother kicks you in the face all night in your small bed under the table, a big RV can seem very small. And, when the dog barks(吠) and Mom plays her country music on the radio—your family is not at its best. What's worse, RVs are always breaking down.

But RV travel can be a great time with the family, too. You can see the country in the comfort of your own "home". You can spend every night in a different scenic(景色的) place, or just stay where you are. You don't have to pay for hotels or restaurants, only gas. But, best of all, you are free to go wherever you want whenever you want in your home-away-from-home.