I wouldn't be surprised at all if you love doing sports. Sports are a very important part of human life. However, some are considered to be more dangerous, such as extreme sports. Because of the danger those sports can lead to, many people believe  they should be banned (禁止). I strongly believe that extreme sports are not a danger and should not be banned. There are many reasons for letting them stay a part of our life. Firstly, extreme sports can increase confidence. Secondly, extreme sports challenge people and develop their skills. And last but not least, extreme sports can add to a person's experience, determination and courage.

    Some people say that extreme sports are much too risky, and there is always a danger of serious injury or even death. But if you want to remove risks, you will have to avoid many other human activities like driving and traveling by plane. Even crossing a road is dangerous!

    Many popular sports in fact can make players injured easily. Football, basketball, gymnastics, figure skating and other sports can lead to bad results. Do you know that football is one of the most dangerous sports? A professional football player gets up to 200 injuries of different kinds every year! And the incidents where a player dies during the match are not very rare.

    Sports do not just have positive physical effects, but they also have mental and social benefits for those who take part in them. I think that taking away elements of risk, danger, and challenge would leave all sports meaningless. Our society will be healthier if more people take part in all types of sports. Banning dangerous sports only limits the freedom of choosing from a wide range of sports that people should feel free to take part in.

    Of course, if you want to take part in an extreme sport, you should always be well prepared. After all, safety comes first.

    On any given day, you can find most 10­year­old boys throwing a ball around outside, riding their bikes, or playing video games. But Braden Baker is different.

    Braden is a hearing impaired (受损的) 5th­grader and has to wear hearing aids (助听器). Unluckily, Braden's dog Chewy found his hearing aids on the floor and destroyed them — not once, but twice — and they had to be replaced. But at $3,500 to $6,000 a pair, Braden's carelessness was costly.

    Braden's mother Ashley sat Braden down and had a long talk about taking better care of his hearing aids, explaining just how much they cost. "I told him that he was lucky we could buy another pair and that some people couldn't afford a new pair," Ashley said.

    Those words clearly stuck in Braden's mind, who realized that not every child who needed hearing aids could afford them. So recently, the 10­year­old took it upon himself to start a GoFundMe page to raise money for those who aren't so lucky.

    Braden made a video to explain why he wanted to raise money. Ashley said, "We weren't really sure how it would turn out. He began with a goal of $1,000. We woke up the next morning and found that it had raised $400."

    This encouraged him to start making even more videos. Fast­forward a few months and Braden's GoFundMe page has raised over $15,000, which Braden donated to the Oticon Hearing Foundation. And that money will be used to help other families buy hearing aids for their children.

    The project has not only taught Braden the value of money, but according to his mom, "he's learned that if you put a small idea into action, amazing things can happen."

    As for Braden's advice to those looking for ways to give back to others? "Don't give up! Any small idea can get really big."

    Rainbows (彩虹) are one of the most beautiful works that nature creates. If you've ever seen one, consider yourself lucky.

    Rainbows can be seen when light passes through raindrops, says Kristin Calhoun, a research scientist studying the conditions of weather.

    When sunlight passes through raindrops, the light bends, as it enters a droplet. As it leaves the droplet, the light separates into different wavelengths (波长). The seven colors — red, orange, yellow, green, blue, indigo and violet — bend in seven different directions. Red light, for example, bends in a different way than violet light. It also explains why rainbows look like an arc (弧). Sometimes, however, rainbows can actually form a circle that you can see in a plane with the right conditions.

    "There is an even better chance when the sun is at a lower level, early or later in the day," Calhoun says. And another key is to face the rain and have your back to the sun.

    "Small showers and storms often form in late afternoon in this area," Calhoun says. "These types of showers often produce heavy rain, but remain isolated (孤立的) over the center of the island."

A．There are lots of stories relating to rainbows.

B．Rainbows are created by light through raindrops.

C．And each wavelength appears as a different color.

D．With the conditions just right, Hawaii gets lots of rainbows.

E．The best time to catch a rainbow is when it's sunny and raining.

F．But they can be seen only if you are in the right place at the right time.

G．This is why the person on the ground sees each color at a different location.