Don't be too surprised if you see a car going down the road without a driver in Beijing these days. It might be one of Baidu's self-driving cars. Last month, Baidu was granted (授予) a license to test its self-driving cars on open roads in Beijing, China Daily reported.

    Self-driving cars have been in development since 2010, when Google announced that it was making such cars. Since then, companies like Tesla, Uber and Baidu have been working to produce and test their own self-driving cars.

    Self-driving cars are expected to revolutionize (革命) the way we get around. They are safer and more environmentally friendly than regular cars. They can remove the stress of driving and allow disabled or blind people to get around more easily.

    But self-driving cars have their own flaws (缺陷) as well. In one test, researchers pointed a laser pointer (激光棒) at the car's sensors (传感器) while it was moving. The car mistakenly thought that the laser beam was in its way and slowed down or changed direction. Flaws like this could be used by people to trick self-driving cars, according to the Guardian.

    The software that is used to direct the cars may not be safe enough, reported Live Science. It may crash (崩溃). When we use our computers or smart phones, they sometimes crash without any reason. But if this happened to a self-driving car, the results could be deadly. Improvements to the software could be a solution to this problem.

    The word 'day' has two meanings. When we talk about the number of days in a year. We are using 'day' to mean 24 hours. But when we talk about day and night. We are using 'day' to mean the time between sunrise and sunset. Since the earth looks like a ball. The sun can shine on only half of it at a time. Always one half of the earth is having day and the other half night. A place. is moved from day into night and from night into day over and over by the spinning(旋转)of the earth. At the equator(赤道)day and night are sometimes the same length, they are each twelve hours long. The sun rises at 6 o'clock in the morning and sets at 6 o'clock in the evening. For six months the North Pole is tilted(倾斜)toward the Sun. In those months the Northern Hemisphere(半球)gets more hours of sunlight than the Southern Hemisphere. Days are longer than nights. South of the equator nights are longer than days. For the other six months the North Pole is tilted away from the SUN. Then the Southern Hemisphere gets more sunlight. Days are longer than nights. North of the equator nights ate longer than days. Winter is the season of long nights. Summer is the season of long days.

    When you carry your heavy schoolbag on the way to school or home, do you know the fact that the heavy schoolbag influences your interest in learning knowledge? Don't worry. You may be able to say goodbye to your heavy schoolbag in the near future.

    Instead of burying(埋葬) your face in an ocean of textbooks, newspapers, magazines and novels, you will soon find that an E-book reader can take the place of them all.

    An E-book reader is a new kind of mini machine designed to hold thousands of text files and display them on the screen as real text printed(印刷) on a paper page.

    In the same way in which the iPod(a kind of MP3) has changed the way people enjoy music, E-book readers could change the way that books are read. Some scientists have predicted that E-books will be used widely in our daily life, especially in schools.

    The size of an E-book reader is the same as that of real books. Its screen is different from that of a computer. It is as thin as a piece of paper. The words on an E-book reader's screen look exactly the same as those on real pages. However, you can do more with an E-book reader than you can with a real book. The reader can change the size of the words and connect to the Internet to download new books.

    Every time when I look at the moon, I wish I could go there. Do you wish you could fly to the moon in a spaceship one day?

For hundreds of years, men have wanted to travel to the moon. When they looked at the moon, they asked many questions. Was the moon hot or cold? Were there any plants or other living things there? There were many, many other questions.

    We know much about the moon now. Scientists have studied the moon for many years and have found out many facts. So far, some men have got to the moon on spaceships.

    Scientists have found that the moon is much smaller than the earth. It is about one quarter the size of the earth. It is traveling round the earth all the time. There are not any plants or other living things on the moon, because there is no air or water there.

    Days and nights on the moon are very long. One day on the moon is as long as two weeks on the earth. One night is also as long as two weeks on the earth. In the day the moon is very hot. At night it is very cold. The moon is much hotter and much colder than the earth.

    There is another surprising thing. On the moon things are not as heavy as they are on the earth. Isn't that interesting? Perhaps one day we can all travel to the moon. It must be great fun.

Elephants are big, but Teensy was the smallest of them. Teensy tried everything she could think of to help herself grow. She ate a lot. However, nothing seemed to 1 .

One day Teensy went with the elephants to have lunch. They stopped in front of some trees and found their favourite green leaves. Teensy raised her nose and tried again and again, but she couldn't reach the branches. Not even the 2 ones!

At the end of the day, Teensy was with the rest of the elephants watching the 3 . But Teensy couldn't see very much. "Excuse me," said Teensy politely, "I'd like to see more than your knees, if you please." But the elephants didn't hear little Teensy. They were too 4 enjoying the sunset. She knew she was too little to walk away by herself, so she sat and imagined what the sunset must look like. "Oh, I guess it is too pretty for words!" she sighed. Teensy was very sad. "Oh, woe is me，" she said. Suddenly, Teensy heard a tiny voice. "What is woe?" the voice said. Teensy looked down and saw a mouse. "Woe means sad," said Teensy. She told the mouse about seeing only elephant5 instead of the sunset. 

"I'm too little," she said. 

"Why? You're not little at all," said the mouse. 

"Do you think so?" replied Teensy, "I'm sorry you're so small. I know how it feels." "Don't be sorry," said the mouse. "I like being small! I can always fit into corners."

"Wow," said Teensy, "so being 6 CAN be good." 

Should friends be different or the same? Different people have different ideas. The following is what four of my classmates say.

My name is Claire. I am outgoing. I like to have friends who are similar to me. Both my best friend Linda and I like traveling. We went to Italy with our families last summer vacation. We stayed there for two weeks. Next year we want to go to Paris.

My name is Mary. I like to have friends who are different from me. My best friend Betty is shorter and more outgoing than me. I am quiet and I like reading very much. Betty likes sports and she plays badminton well.

I'm Peter. I like to have friends who are like me. It can be very helpful. I'm a little quiet and my good friend Rick is quiet, too. Sometimes I don't know what to do with my problems and he can tell me what I should do, because he knows about me better than people who are different from me.

I'm Bill. I have both kinds of friends. I think it is important. That makes my life more interesting.