Water is the “life blood” of our earth. It is in every living thing. It is in the air. It runs through mountains and valleys. It forms lakes and oceans. Water is everywhere.

    Nature has a great water system. Rain water finds its way to streams and the oceans.

    Here at the mouth of a river there is much important plant and animal life. Pollution destroys this life, so we have to clean out streams and rivers. Man has to work with nature--not against it.

    A small group of people around the world have started implanting(移植) microchips to link the body and the computer.

    Mr. Donelson and three friends, who had driven 100 miles from their homes in Loockport, New York, to have the implants put in by Dr. Jesse Villemaire, whom they had persuaded to do the work, are part of a small group, about 30 people around the world, who have independently put in microchips into their bodies, according to Web-based reports.

    At a shop William Donelson was having a four-millimeter-wide needle put into his left hand. “I'm set,”he said with a deep breath. He watched as the needle pierced(刺穿) the fleshy webbing between his thumb and a microchip was set under his skin. At last he would be able to do what he had long imagined: strengthen his body's powers through technology.

    By putting the chip inside—a radio frequency identification device (RFID)—Mr. Donelson would have at his fingertips the same magic that makes safety gates open with a knock of a card, and bridge and tunnel traffic flow smoothly with an E-Zpass. With a wave of his hand he plans to connect with his computer, open doors and unlock his car.

    Implanting the chip was relatively simple task but very meaningful to Mr. Doneselson, a 21-year-old computer networking student so interested in the link between technology and the body that he has data-input jacks(数据输入插空) inside his body. They might lead to an imagined future when people can be connected directly into computers. His new chip is enclosed in a glass container no bigger than a piece of rice and has a small memory where he has stored the words “Technology”.

    Some doctors have done the piercing in people's homes, and others have implanted chips in their offices after patients signed forms showing the fact that long-term studies have not been done on their safety. Piercers treat the implants much like any other medical operation steps, instructing people to keep the site dry, and advising them that swelling and redness should last a week.

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    On a Saturday morning earlier this September, the world got its first look at the Strati. This electric vehicle is unlike any other currently on the road. It rolls on four wheels, but its body and chassis(底盘) weren't built in a factory. Instead, Strati's designers used a technology called 3-D printing. It created those parts of the car in one piece, from the ground up.

    “Compared to a typical vehicle on the road, the Strati definitely looks different,” says Greg Schroeder, a senior research engineer at the Center for Automotive Research in Ann Arbor, Mich. He did not work on the new car. His organization studies trends and changes in th e auto industry.

    It took 44 hours to print the new car at the International Manufacturing Technology Show in Chicago. Over the next few days, the car's designers installed additional parts. These included the car's engine, brakes and tires. Then, early on September 13, Jay Rogers climbed into the car, started its engine and drove the vehicle onto the street. Rogers helped found Local Motors. It's the Arizona-based company behind the Strati. Two weeks later, his team printed a second Strati, and just as fast, at a fair in New York City.

    Justin Fishkin, a local Motors official, sees the Strati as a window into the future. Today, car buyers are limited in their choice of a vehicle. They can order only what car companies have already designed. But in the future, he says, you may be able to design your own car online and then get it printed to order.

    Manufacturing experts say 3-D printing has begun to revolutionize how they make things. The technology has been around for decades. But these machines used to be so expensive that only large companies could afford them. In the last few years, though, that has changed. Many of the machines are now inexpensive enough for small companies—or even individuals —to own. Some local libraries make them available to the public. High Schools are beginning to use them in classrooms. Wide access to these printers means people can now design and print a wide variety of new things.

    The car's printer is a one-of-a-kind device.

    The technology behind the 3-D printer used in Chicago is an example of additive manufacturing. This proce ss builds solid objects, slice by slice, from the bottom up. (“Strati” means layers, in Italian.) A mechanical arm moves a nozzle from one side to another, back and forth. As it moves, the nozzle deposits a liquid—often melted plastic or metal (but it could be food, concrete or even cells) —that quickly hardens or bonds to become solid or semi-solid. This creates a single, thin layer. Once a layer is complete, the printer starts depositing the next one.

     “There's a lot of interest in 3-D printing in the auto industry,” says Schroeder. Right now, the technology is particularly useful for building models of cars or car parts.

    To compete with current auto manufacturers, the 3-D printer would have to increase in a hurry, Schroeder says. By contrast, he notes, a Ford F-150 pickup truck rolls off an assembly line at a rate of roughly one per minute. To print as many Stratis would require many more printers. Schroeder says he doesn't see 3-D printing soon taking over for such high-volume manufacturing. But, he adds, “Who knows what will h appen in the long term?”

    Scientists at Oak Ridge National Laboratory in Tennessee designed the 3-D printer used in Chicago. Lonnie Love, a research scientist at the lab, led the effort.

    Additive manufacturing often is slow and expensive. It also may produce materials that are unreliable, Love says. So for two years, his team searched for ways to make 3-D printing better. They built new machines and tested them over and over.

    All of that work paid off: their new machine is fast and uses less expensive material than earlier printers. In addition, it prints a plastic embedded with fibers of carbon to produce a stronger material. This helps ensure the material won't crack or break under pressure.

    Who could have imagined that a treadmill（跑步机）on wheels would one day become a thing?!? Lopifit is an unusual means of transportation that allows you to power an electric bicycle by walking on a treadmill.

Lopifit founder Bruin Bergmeester says it all started when he asked himself the question "How can I use a treadmill outdoors?" He finally came up with a new design, adding an electric motor, and the Lopifit was born. It's similar to an electric bicycle in that the motor only works when the rider puts power in as well. The Lopifit senses when you walk on the treadmill and uses the motor to turn a drive chain at the back of the treadmill, helping you reach a top speed of 17 miles per hour.

    To use the Lopifit, simply turn on the battery（电池）and use your foot to slide the treadmill backwards and start the motor. Then get on and enjoy the ride! If you need speed, just walk on the treadmill, and if you want to coast（惯性滑行）, all you have to do is stay still and admire the view. To stop, you have two hand breaks.

    The Lopifit first hit the streets in 2014 and, unsurprisingly, became a hit overnight. That was actually quite challenging for the company, because it started getting calls for orders, but it was nowhere near ready for mass production. The unique treadmill bicycle could be bought this year, and Lopifit is struggling to keep up with demand, although the price is up to $2,115.

    Some people consider this means of transportation stupid and unnecessary, although there is a very loyal fan-base of so-called Lopifitters. They simply believe that if you're going to walk, you might as well do it the old-fashioned way.

But the Lopifit does have the special advantage of helping you "walk" really fast without much effort, or walking at cycling speed, if you will.

    Each year, hundreds of thousands of wild animals around the world are killed in trophy hunting—the organized shooting of animals for pleasure. The hunters then bring parts of the animal home with them as their "trophy" to remember the hunting.

    Trophy hunters pay big money to kill animals. Some of the money goes to helping wildlife protection. Trophy hunting also attracts business, which encourages people to preserve land and breed(饲养) animals that would otherwise be endangered. Cathy Dean, head of the Save the Rhino Charity, says that at the start of the 1900s there were only 50–100 southern white rhinos. Now, there are around 18,000. This is partly because some of them were raised specially for trophy hunting.

    But things don't usually go on one way. According to WWF, elephant populations have fallen from 1.3 million to just over 400,000 since the 1980s. Over the same period, hunters from around the world have taken home more than 100,000 African elephant trophies. Trophy hunting is not illegal(非法的) but unfair on the animals. In 2015, Cecil the lion was shot by a US trophy hunter. Cecil was a beloved lion in Zimbabwe, Africa. Cecil was lured with bait(诱饵), shot with an arrow and struggled in blood for more than ten hours before his hunters tracked and finished killing him. His son, Xanda, met a similar fate two years later.

    Cecil's death caused worldwide outrage and protests(反抗) against trophy hunting. Countries including Australia, France and the Netherlands banned(禁止) the import of lion trophies—they stop hunters from being allowed to bring home parts of the animal they kill. They believe that people will stop trophy hunting because the activity might lose its attraction if hunters can't bring their trophies home.

    The UK Government said that it would consider a ban on trophy-hunting imports by 2017, but no action had been taken. In April 2019, a letter by protesters against trophy hunting was sent to the UK government asking to ban trophy-hunting imports. On 7 May, the official in charge of the environment, Michael Gove, said that the UK would not ban the imports for the time being. This left the world in a state of a shock. Hopefully the UK will place a ban on trophy-hunting imports, which would be an important message and inspire others to treat animals better. We're waiting for the day to come.