We usually believe what our brain tells us, but there are some amazing facts which show that the brain tricks us. As a result, we think we can see something that is not actually there or we ignore（忽视）things that actually are there.

 Scientists Daniel Simons and Christopher Chabris have researched this phenomenon（现象）, which they call “change blindness”. Their experiments show how we sometimes just do not see what is in front of our eyes because           42          .

 Here is one of their most famous experiments. In this experiment, the participants（参与者）were shown a video of two groups of people (one group in white T-shirts and one group in black T-shirts) who passed basketballs around in a hallway. Each group had three members. Simons and Chabris asked the participants to count how many times the white team passed the ball. While the two teams were passing their balls around, a person dressed up as a big bear walked through the group and stopped to look at the camera. Simons and Chabris found that about half of the research participants did not notice the big bear.

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    For many smart phone users, especially young people, scanning QR Codes（二维码）has become a new and convenient life style these days. In fact, the QR Code was created in Japan in 1994, but until 11 years later, it was first used in China. It soon became popular around the country. The QR Code is much-loved because it provides a way to get to website more quickly. By scanning QR Codes, people can do lots of things, such as adding new friends, getting information, downloading Apps, shopping and so on. As for the shopping websites, there are usually more sales, including coupons（优惠券）for the phone users. The QR code is so common that people can scan them everywhere. We interviewed 100 people, and here are the results.

    Want to be an astronaut?Then“study hard，stay healthy and have perseverance”!

    This is what Chinese astronauts Fei Junlong and Nie Haisheng said in Hong Kong．Fei，Nie and leading engineers of Shenzhou VI visited Hong Kong from November 27 to 30，2010．

    They talked with primary，secondary and college students．Kids were interested in the astronauts' space lives．They asked questions like “Did you see the Great Wall from space?”Fei and Nie said they didn't see the Great Wall．But they felt excited when they passed over China，including Taiwan．The Taiwan Island looks very beautiful，like jade．

    Young people wanted to know how the astronauts developed(发展)their careers(职业)．“How did you decide to be astronauts when China's space industry is still at the beginning?”spoke a young woman．The astronauts said it was because of their love of flight and the need of the nation．They said their love of flight could be seen from their children's names．Nie's daughter is named Nie Tianxiang，which means“flying up high”．Fei's son is called“Fei Di”，which sounds like“Feidie”，meaning UFO．

    Many people like to travel by plane, but I don't like it because an airport is usually far from the city. You have to get there early and wait for hours for the plane to take off and it is often late. You can't open the window. You can't choose the food. Planes are fast, but it still takes hours to get out of the airport and into the city.

    I like traveling by train. I think trains are safe. Railway stations are usually in cities. When you are late for a train, you can catch another one. You can walk around in the train and open the windows. You can see many interesting things on your way. I know it takes a little more time.

    I also like cars. You can start your journey when you want to, and you don't need to get to a railway station or a bus stop. Also you can take many things with you in a car. But sometimes there are too many cars on the road.