More and more people like bicycling and it is no surprise. It is fun, healthy and good for the environment. Maybe that's why there are 1.4 billion bicycles and only 400 million cars on roads worldwide today. Bikes can take you almost anywhere, and there is no oil cost!

    Get on a bicycle and ride around your neighbourhood. You may discover something new all around you. Stopping and getting off a bike is easier than stopping and getting out of your car.

    You can bike to work and benefit (受益) from the enjoyable exercise without polluting  the environment. You don't even have to ride all the way. Folding (折叠) bikes work well for people who ride the train. Just fold the bike and take it with you. You can do the same on an airplane. A folding bike can be packed in a suitcase. You can also take a common bike with you when you fly. But be sure to look for information by getting on airline websites. Not all airlines are bicycle-friendly to travellers.

Health Benefits of Bicycling:

    It helps to prevent heart diseases.

    Bicycling helps to control your weight.

    A 15-minute bike ride to and from work three times a week burns off five kilos of fat in a year.

    Bicycling can improve your mood (心情).

    Exercise like bicycling has been shown to make people feel better, more relaxed and self-confident.

    Bicycling is healthier than driving.

Four apps for students to learn English

    Quizlet

    Quizlet is a learning app—a computer program you use on your mobile device. It can help users build and test their knowledge of English words and terms. Quizlet has word sets for millions of subjects. And, it is quickly becoming a useful mobile tool for language learners.

    Socrative

    In Socrative, teachers can create timed learning games. In class, students compete individually or as part of a team against classmates. One game students love is called space Race. In this game, if a team answers a question correctly, their rocket moves forward. This team whose rocket gets to the end first wins. Also, teachers can use Socrative as an “exit ticket, ”a question they can ask students about what they learned in that day's class. Students write their answers on their mobile devices. Then, the teacher can show the answers on a shared video screen.

    QR Codes

    AQRCodeisakindofsignthatasmartphonecanreadwithitscamera. When your phone camera reads a QR code, it takes you to a website, image, video or anything you want to share. For example, one will take you to the VOA Learning English website.

    Evernote

    Evernote lets users store and share notes, images and recordings in one place. Teachers can also use Evernote to give homework.

    The town of Green Bank, West Virginia, is the site of the largest radio telescope in the world, so Internet connections and anything else that can create electromagnetic(电磁的) waves, such as smart phones and microwave ovens, are banned.

    Green Bank is frozen in time, somewhere in the 1950s, because there's a 33,000-square-kilometer zone of silence due to the telescope. Cell phone towers are forbidden.

    The closer you get to the telescope, the greater the restrictions. There's a 16-kilometer radius(半径) around the observatory where radio-controlled items, even toys, cannot be used.

    Telescope employees even work in a special room that blocks electromagnetic waves from leaving it. “Here imagine a submarine(潜艇), water cannot get inside, and so this room is an electric submarine. No electromagnetic waves can get into this room, just as you can't go beyond it,” Michael Holstein, an observatory officer, said.

    The size of a football field, the telescope is so sensitive that it could pick up signals sent from an alien world. And scientists can't wait for that to happen.

    “All the signals that we now receive with the help of telescopes are signals that come from cosmic objects — stars, galaxies. We have not yet received anything from intelligent civilizations,” scientist Richard Lynch said.

    Local people respect the work of the scientists. “Yes, we are different. Many would say that we live the old-fashioned way, in the past. But for us, it's just the way of life that we have always lived,” Sherry said.

    “When we want to meet friends, we just call each other on a wire phone. And instead of sitting in front of your screen, we talk, we go fishing, to the mountains,” resident Sherry said.

    For the latest news, residents read the weekly local newspaper. When she's looking for a phone number, Sherry reaches for the phone book.

    And instead of Facebook, Sherry enjoys daily conversations with her customers. In this town, everyone knows each other and communication is face to face.

    In February, 2015, a South Korean woman was sleeping on the floor when her robot vacuum ate her hair, forcing her to call for emergency help. It surely isn't what Stephen Hawking warned us that intelligent devices “mean the end of the human race”. But it does highlight one of the unexpected dangers of inviting robots into our home.

    There are many examples of intelligent technology going bad, but more often than not, they involve cheating rather than physical danger. Meanwhile, increasing evidence suggests that we, especially children, tend to tell our deepest, darkest secrets to human robots. So how do we protect ourselves from giving-away code?

    Once you've invited a robot into your home, you need to manage your expectations. Movies and marketing may have told us to expect deep interaction with robots friends but we've still got a long way to go before they are as socially aware as described. Given the gulf between expectation and reality, it's important to avoid being tricked.

    The message is clear: as robots became increasingly connected to the internet, and able to respond to natural language, you need to especially cautious about figuring out who or what you are talking about.

    We also need to think about how information is being stored and shared when it comes to robots that can record our every move. Some recording devices may have been designed for entertainment but can easily be adapted for more dangerous purposes. Take Nixie, the wearable camera that can fly off your wrist at a moment's notice and take shots around you in the air. It doesn't take much imagination to see how such technology could be taken advantage of.

    If the technology around us is able to record and process speech, images and movement, or listen secretly to us, what will happen to that information? Where will it be stored? Who will have access?

    So, what is the safest way to welcome robots into our homes, public spaces, and social lives? We should be cautiously optimistic that intelligent machines could become enriching companions, while acknowledging that we need to determine strict boundaries for robots. There should be someone to turn to should your robot commit a crime, steal your card... or try to eat your hair.

    When he was 22, Rob Stewart traveled the world for four years. He wanted to call attention to the mistreatment of sharks. His 2007 film, Sharkwater, documents the cruel practice of removing sharks' fins (鳍) for money and leaving the animals to die. In his latest documentary, Revolution, Stewart takes on an even bigger challenge: climate change.

    The Canadian filmmaker says that climate change has harmed people and places everywhere: "It is stronger than any government or organization. If we educate people, they will make better decisions about protecting natural resources. "

    According to a recent report on climate change, "The atmosphere and ocean have warmed, the amounts of snow and ice have reduced, and sea levels have risen." These developments are endangering crops, wildlife, fish, and even people.

    Stewart says that the consequences of climate change will be irreversible unless people take action, especially young people."It's up to kids to be the moral compass (道德指南) of society," he believes, "and say, 'Guys, this is not right.'"

    Many kids took action after seeing Sharkwater. Elementary school students in the Northern Mariana Islands, for example, got their local government to ban the sale of shark fins.

    Felix Finkbeiner, 17, of Germany is also part of the "revolution" to save the planet. In 2007, Felix started a youth group called Plant-for-the-Planet, whose motto is "Stop Talking. Start Planting." The group raises money to plant trees. So far, Plant-for-the-Planet has planted nearly 200 trees around the world. "Future generations are the ones who will be suffering the most from inaction (无作 )," Felix says. His goal is to plant millions of additional trees.

    "When we started four years ago," Felix tells Stewart in Revolution, "we thought we had to save the polar bear. We thought we had to save the environment. But soon after, we found out that it's about our future, that we have to save our own future."

    Close your eyes for a minute and imagine what life would be like if you had a hundred dollars less. Also imagine what it would be like spending the rest of your life with your eyes closed. Imagine having to read this page, not with your eyes but with your finger-tips.

    With existing medical knowledge and skills, two-thirds of the world's 42 million, blind should not have to suffer. Unfortunately, rich countries possess most of this knowledge, while developing countries do not.

    ORBIS is an international non-profit organization which operates the world's only flying teaching eye hospital. ORBIS intends to help fight blindness worldwide. Inside a DC-8 aircraft, there is a fully-equipped teaching hospital with television studio and classroom. Doctors are taught the latest techniques of bringing sight back to people there. Project ORBIS also aims at promoting peaceful cooperation among countries.

    ORBIS tries to help developing countries by providing training during three-week medical programs. ORBIS has taught sight-saving techniques to over 3,000 doctors and nurses, who continue to cure tens of thousands of blind people every year. ORBIS has conducted 17 plan programs in China so far. For the seven to ten million blind in China ORBIS is planning to do more for them. At the moment an ORBIS is working on a long-term plan to develop a training center and to provide eye care service to Shanxi Province. ORBIS needs your help to continue their work and free people from blindness.

    For just US$38, you can help one person see; for $380 you can bring sight to 10 people; $1,300 helps teach a doctor new skills; and for $13,000 you can provide a training program for a group of doctors who can make thousands of blind people see again. Your money can open their eyes to the world. Please help ORBIS improve the quality of life for so many people less fortunate than ourselves.