What would it be like to walk on Mars? If you could build the highest building in the world，what would it look like? Do you dream of being the next J. K. Rowling? This summer, you can experience all of these things, and more. All you need is an Internet connection and your imagination.

    A recent study by the Kaiser Family Foundation found that kids spend an average of 1 hour and 29 minutes online each day. Many kids like to use that time to chat with friends, play games or check e­mails. But the next time you get on the Web, try exploring the world instead. “With the Internet，you can go back 11,000 years in time，or go 11,000 kilometers across the planet.” said Russell, Web search expert of Google. “The whole scope of history and the world is open to you.”

    There is a wealth of information to be found online. For example, if your family is going on vacation somewhere, do a quick online search on the area before you even get in the car. “What's the background of the place; what's the history？” says Russell. “I like to tell my kids, ‘Whenever you have a question, whenever you have a doubt, search it out.'”

    Ready to launch a virtual journey of your own? Here are a few starting points to get you thinking and to help you on your way. You can invite your parents along for the ride, too. Always ask for permission before downloading programs and software onto your computer. And check with a parent or an adult before visiting any new Web site.

    Navigate the world in 3­D with Google Earth. Begin in outer space and zoom (快速移动) into the streets of any city, from Hong Kong to San Francisco. Or visit ancient monuments, watch the changing rainforests over time, and dive underwater to explore tropical reef.

    With the Moon in Google Earth tool, you can walk in Neil Armstrong's famous footsteps. Take a guided tour of the moon's surface with Armstrong's fellow shuttle mate astronaut Buzz Aldrin.

    When you're exploring that part of the solar system, hop on over to the Red Planet with Google Mars. There, you can move very quickly around the surface and see images from the Mars Rovers.

    A team of engineers at Harvard University has been inspired by Nature to create the first robotic fly. The mechanical fly has become a platform for a series of new high-tech integrated systems. Designed to do what a fly does naturally, the tiny machine is the size of a fat housefly. Its mini wings allow it to stay in the air and perform controlled flight tasks.

    “It's extremely important for us to think about this as a whole system and not just the sum of a bunch of individual components (元件),” said Robert Wood, the Harvard engineering professor who has been working on the robotic fly project for over a decade. A few years ago, his team got the go-ahead to start piecing together the components. “The added difficulty with a project like this is that actually none of those components are off the shelf and so we have to develop them all on our own,” he said.

    They engineered a series of systems to start and drive the robotic fly. “The seemingly simple system which just moves the wings has a number of interdependencies on the individual components, each of which individually has to perform well, but then has to be matched well to everything it's connected to,” said Wood. The flight device was built into a set of power, computation, sensing and control systems. Wood says the success of the project proves that the flying robot with these tiny components can be built and manufactured.

    While this first robotic flyer is linked to a small, off-board power source, the goal is eventually to equip it with a built-in power source, so that it might someday perform data-gathering work at rescue sites, in farmers' fields or on the battlefield. “Basically it should be able to take off, land and fly around,” he said.

    Wood says the design offers a new way to study flight mechanics and control at insect-scale. Yet, the power, sensing and computation technologies on board could have much broader applications. “You can start thinking about using them to answer open scientific questions, you know, to study biology in ways that would be difficult with the animals, but using these robots instead,” he said. “So there are a lot of technologies and open interesting scientific questions that are really what drives us on a day to day basis.”

    Biologists believe that love is fundamentally a biological rather than a cultural construct, because the capacity for love is found in all human cultures and similar behavior is found in some other animals. In humans the purpose of all the desire is to focus attention on the raising of offspring. Children demand an unusual amount of parenting, and two parents are better than one. Love is a signal that both partners are committed, and makes it more likely that this commitment will continue as long as necessary for children to reach independence. But what does science have to say about the notion of love at first sight?

    In recent years the ability to watch the brain in action has offered a wealth of insight into the mechanics of love. Researchers have shown that when a person falls in love, a dozen different part of brain work together to release chemicals that trigger feelings of euphoria, bonding and excitement. It has also been shown that the unconditional love between a mother and a child is associated with activity in different regions of the brain from those associated with pair-bonding love.

    Passionate love is rooted in the reward circuitry of the brain—the same area that is active when humans feel a rush from cocaine. In fact, the desire, motivations and withdrawals involved in love have a great deal in common with addiction. Its most intense forms tend to be associated with the early stages of a relationship, which then give way to a calmer attachment form of love one feels with a long term partner.

    What all this means is that one special person can become chemically rewarding to the brain of another. Love at first sight, then, is only possible if the mechanism for generating long-term attachment can be triggered quickly. There are signs that it can be. One line of evidence is that people are able to decide within a second how attractive they find another person. This decision appears to be related to facial attractiveness, although men may favor women with waist-to-hip ratio of 0.7, no matter what their overall weight is. (This ratio may indicate a woman's reproductive health.)

    Another piece of evidence comes from work by a psychologist at Ben-Gurion University, who found in a survey that a small percentage (11%) of people in long-term relationships said that they began with love at first sight. In other words, in some couples the initial favorable impressions of attractiveness triggered love which sustained a lengthy bond. It is also clear that some couples need to form their bonds over a longer period, and popular culture tells many tales of friends who become lovers.

    One might also assume that if a person is looking for a partner with traits that cannot be quantified instantly, such as compassion, intellect or a good sense of humor, then it would be hard to form a relationship on the basis of love at first sight. Those more concerned with visual appearances, though, might find this easier. So it appears that love at first sight exists, but is not a very common basis for long-term relationships.

    There are many places to go on safari（观赏野生动物）in Africa, but riding a horse through the flooded waters of Botswana's Okavango Delta must rank as one of the world's most exciting wildlife journeys.

    Several safari camps operate as the base for this adventure, providing unique rides twice a day to explore deep into the delta. The camps have excellent horses, professional guides and lots of support workers. They have a reputation for providing a great riding experience.

    The morning ride, when the guides take you to beautiful, shallow lakes full of water lilies, tends to be more active. It is unlike any other riding experience. With rainbows forming in the splashing water around you and the sound of huge drops of water bouncing off your body and face. It is truly exciting. You are very likely to come across large wild animals, too. On horseback it is possible to get quite close to elephants, giraffes and many other animals. The sense of excitement and tension levels rise suddenly though, as does your heart rate, as you move closer to them.

    In the evening, rides are usually at a more relaxed and unhurried pace. With golden light streaming across the grassy delta and the animals coming out to eat and drink____though they are, rides at this time of day are still very impressive. As the sun's rays pass through the dust kicked up by the horses, the romance of Africa comes to life.

    Back at the camp you can kick off your boots and enjoy excellent food and wine. Looking back on your day, you will find it hard to deny that a horseback Safari is as close as you will ever come to answering the call of the wild.

    Lily went to London with her parents for a two-week vacation. She sent postcards to her friends.

    "What kind of rubbish are you?" This question might normally cause anger, but in Shanghai it has brought about complaints over the past week. On July 1st, the city introduced strict trash-sorting regulations that are expected to be used as a model for our country. Residents must divide their waste into four separate kinds and put it into specific public bins. They must do so at scheduled times, when monitors are present to ensure compliance（服从）and to inquire into the nature of one's rubbish.

    Violators face the possibility of fines and worse. They could be hit with fines of up to 200 yuan ($29). For repeat violators, the city can add black marks to their credit records, making it harder for them to obtain bank loans or even buy train tickets.

    Shanghai authorities are responding to an obvious environmental problem. It generates 9 million tonnes of garbage a year, more than London's annual output and rising quickly. But like other cities in China, it lacks a recycling system. Instead, it has relied on trash pickers to sort out the waste, picking out whatever can be reused. This has limits. As people get wealthier, fewer of them want to do such dirty work. The waste, meanwhile, just keeps piling up. China produces 80 billion pairs of disposable(一次性的)chopsticks a year.

    Many residents appear to support the idea of recycling in general but are frustrated by the details. Rubbish must be divided according to whether it is food, recyclable, dry or hazardous(有害的), the differences among which can be confusing, though there are apps to help work it out. Some have complained about the rules surrounding food waste. They must put it straight in the required public bin, forcing them to tear open plastic bags and toss it by hand. Most upset are the short windows for throwing trash, typically a couple of hours, morning and evening. Along with the monitors at the bins, this means that people go at around the same time and can keep an eye on what is being thrown out; no one wants to look bad.