A taxi hit a truck. A policeman spoke to the taxi driver and to the truck driver. He also spoke to Tom. He was a witness (目击者). This is what they said.

    TRUCK DRIVER: I was driving from the airport to Newton. A car crossed the road, so I slowed down. I did not stop. A taxi hit the back of my truck. Nobody was seriously hurt but both cars were damaged（受损害）.

    TAXI DRIVER: I was driving behind a truck a few kilometers from Newton. The truck stopped suddenly. The driver did not give me a warning (警告). I was driving very slowly. I could not pass the truck because there were two cars coming near from Newton. My taxi hit the truck, and some glass cut my left hand.

TOM: I was watching the traffic about a kilometer from the airport. A truck was going to Newton. It was not going very quickly. There was a taxi about two hundred meters behind the truck. It was going fast. When the truck slowed down, the taxi hit it. The taxi driver was not looking at the truck. He was looking out of the window at something. My friend saw the accident, too.

    Tom's friend spoke to the policeman and agreed with Tom.

    Do you know what the hump(驼峰) of a camel is used for? If you answered to store water, guess again. In fact, a camel's hump is a place for storing fat.

    Most animals, including humans, store fat throughout their bodies, under their skin. But camels store their fat in one place, their hump. A hump can weigh as much as 80 pounds. Why do camels keep their fat this way? The answer is most likely because of their environment. Camels can go up to two weeks without eating because they have this fat to live off.

    Also camels are great at handling(处理，应付) changes in body temperature. Their humps can help the camels keep cooler. Their coats also help them adapt(适应) to the heat. While the coat is thick, it reflects(反射)the sunlight and protects the camel from the heat that rises off the desert sand.

    There are two kinds of camels, those with one hump and those with two humps. Camels with one hump are called Dromedary or Arabian camels. They live in the dry deserts in West Asia. Camels with two humps are called Bactrian camels. They live in Central and East Asia.

    Besides their humps, camels have a lot of interesting facts. They can live between 40~50 years. They can carry about 400 pounds and run up to 40 miles per hour. It's true that camels can go long time without drinking water, and they can drink about 26 gallons of water at a time. Camels can also close their nostrils(鼻孔). So whether a camel has one hump or two, it is one amazing animal that is very well adapted to its environment.

    Since the first person walked on the moon in 1969, technology has greatly helped space exploration. In recent years scientists have built a special robot to accompany astronauts on space missions (任务). Because this robot looks and moves like a person, scientists call it a humanoid robot. The latest model of the humanoid robot is known as R2, short for Robonaut 2.

    R2 was first launched into space on February 24, 2011. It was built by the National Aeronautics and Space Administration (NASA) and the car producer General Motors (GM).

    R2 weighs 330 pounds and costs $2.5 million to build. It has arms and a head- filled with vision equipment—but no legs. Its "brain", or computer, is in its stomach. R2's arms can hold 20 pounds. Each bendable finger has 5 pounds of grasping force. R2's hands are also skillful. Since its hands are shaped like human hands, R2 can use human tools to complete tasks traditionally performed by astronauts." Astronauts absolutely have their day packed from the minute they wake up until they go to bed. If Robonaut can provide just an hour's worth of relief to the astronauts doing something they don't want to do, that would make it worth it right there," says Nic Radford, the deputy project manager of R2.

    One advantage of working with R2 will be that ii can't complain about its work! Astronauts will also appreciate the fact that the robot can perform its duties without constant supervision (监管). R2 can be assigned a task and then checked on periodically. If R2 does not complete a task correctly, astronauts will be able to make minor adjustments to adapt (适应) the robot's behavior so that the task gets done right.

    R2 is still in the design stage of development, which means that scientists are frequently testing it and looking for ways to improve it. Right now, humanoid robots do not have the protective equipment needed to work outside the space station. As technology advances, humanoid robots will be able to help astronauts with dangerous tasks as well as routine ones.

    In the future, humanoid robots will be astronauts' eyes in space, going to places considered too difficult or unsafe for astronauts to explore. Some of them will be mounted on wheels to explore the surface of planets or asteroids (小行星). The robots will be able to send back videos and help astronauts gather information about the atmospheres of these places.

    One outcome of using these humanoid robots will be a greater understanding of the interaction between humans and robots. NASA engineers believe that when humans and robots combine forces and work together, the results will be better than what either could achieve alone. John Olson, a director at NASA headquarters in Washington, D.C, says that the project will allow us to go farther and achieve more than we can probably even imagine today.

    Have you ever had the strange feeling that you were being watched? You tum around and, sure enough, someone was looking right at you!

Parapsychologists(R y3)say that humans have a natural ability to sense when someone is looking at them. To research whether such a "six sense" really exists, Robert Baker, a psychologist(心理学家) at the University of Kentucky, did two experiments.

    In the first one, Baker sat behind unknowing people in public places and stared at the backs of their heads for 5 to 15 minutes. The subjects(受试者)were eating, drinking, reading, studying, watching TV, or working at a computer. Baker made sure that the people could not tell that he was sitting behind them during those periods. Later when he questioned the subjects, almost all them said they had no sense that someone was staring at them.

    For the second experiment, Baker told the subjects that they would be stared at from time to time from behind in a laboratory setting. The people had to write down when they felt they being stared at and when they weren't. Baker found the subjects were no better at telling when they were stared at and when they weren't.

    Baker concludes that people do not have the ability to sense when they are being stared at. If people doubt the outcome of his two experiments, said Baker," I suggest they repeat the experiments and see for themselves

    Water is the1of all the things we eat and drink. Not many people understand this but2quite true. The human body3go without food for a long time. We've got many examples for this. Yet two4three days without water can usually make people5. Man can't live6water.

    Many people don't understand how7water the human body needs8work well, and many people, especially young people, do not drink enough,9in very hot weather. Our body is mostly water, about 65% to 75%. That is to say about two thirds of our body is water. When we do sports, some of the water will get away from our body.10we don't drink some water, we won't have enough water. If we don't have enough water, we'll feel tired and many of us will get ill. So you know how important water is to us.