The idea of being able to walk on water has long interested humans greatly. Sadly, biological facts prevent us ever accomplishing such a thing without artificial aid—we simply weigh too much, and all our mass pushes down through our relatively small feet, resulting in a lot of pressure that makes us sink.

    However, several types of animals can walk on water. One of the most interesting is the common basilisk Basilicus basilicus, a lizard (蜥蜴)native to Central and South America. It can run across water for a distance of several meters, avoiding getting wet by rapidly hitting the water's surface with its feet. The lizard will take as many as 20 steps per second to keep moving forward. For humans to do this, we，d need huge feet that we could bring up to our ears in order to create adequate w hitting. ''

    But fortunately there is an alternative : cornflour. By adding enough of this common thickening agent to water (and it does take a lot), you can create a “non-Newtonian” liquid that doesn't behave like normal water. Now, if the surface of the water is hit hard enough, particles(粒子）in the water group together for a moment to make the surface hard. Move quickly enough and put enough force into each step, and you really can walk across the surface of an adequately thick Liquid of cornflour.

    Fun though all this may sound, it's still rather messy and better read about in theory than carried out in practice. If you must do it, then keep the water wings handy in case you start to sink--and take a shower afterward!

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    Hello. I'm Jan from Mrs. Lake's class. My class wants to work together to help the public. We think we have found a great way to do this. Last month we did a class project on the highways near our town. We learned about the Adopt-a-Highway Program. This program brings people together to pick up litter along the roads. We think it would be a great idea for all students in our school to join the program and adopt（收养） a highway.

    Adopting a highway is not like adopting a pet. When a highway is adopted, only part of the highway is cared for by a group of people. The group agrees to work every week to keep its part of the highway clean. Each group gets its own sign that has the name of the group printed on it. The sign is put up at the side of the road. This sign lets drivers know who is keeping that area of the road clean.

    The Adopt-a-Highway Program is a great way for people to help their environment look nicer. Also, the government does not have to send out as many road workers. This saves money. Finally, people may try harder to keep roads clean if they see people, especially teenagers like us, cleaning them up.

    We will need helpers to care for our adopted highway. If you want to feel great and keep our roads clean，please come with your parents to the meeting next week. We will meet in Mrs. Lake's room on Wednesday at 6:00 P.M. At the meeting, we will talk about which roads are the dirtiest as a result of people's unkind acts. Then we'll try to pick an area to adopt and clean.

    I look forward to seeing you at the meeting. Remember to keep our roads clean!

    Some of the best things in life don't happen until you grow old enough to recognize them. I can say that about tea.

    I didn't start to drink tea until I was 35. What happened before that? The first time I felt a genuine urge to drink tea was in 2003, when I stayed briefly in the United Kingdom. After a time of consuming local food, I started to really like strong black tea. Although it was too strong to my tongue, I felt it was a necessity because it was comforting to my body.

    I took packs of green teas with me as gifts but was disappointed to find my British friends preferred much stronger black teas from Sri Lanka. Later I learned that although people know China for its teas, it ranks only third among the world's black tea exporters, after Sri Lanka and Kenya.

    After I came back to China and started to cover food stories, I met friends in the tea-drinking circle and learned more. Although the majority of the rest of the world drinks black tea, which the Chinese call“red tea”, China produces and drinks mostly green teas.

    I feel lucky to be Chinese because of the great variety of teas available in the country. It is estimated that there are more than 2,000 teas in China if you divide them geographically, including more than 600 locally famous brews. A more simple way to categorize (分类) is by color and extent of fermentation (发酵). That comes down to six main categories—green, white, yellow, dark-greenish (oolong), red and black teas.

    Tasting teas can be compared to our lives. They can be plain and predictable but sometimes they are full of pleasant surprises. Occasionally they can even seem too good to be true. The best thing is, you know there's always more to explore.

    Kids are natural scientists. That may be why they ask so many questions.

    Younger kids take up science and math with amazing enthusiasm, yet as they get older they often lose their excitement. Children look on scientific exploration as play, but as they get older they start to connect it with big heavy books, long worksheets and a lot of really confusing words.

    What a tragedy! We had their attention, they were listening, they were participating, they were learning and then we lost it to boredom.

    We need our kids to play more. More play brings up basic scientific concepts(概念). Being familiar with basic scientific concepts brings about exploration which leads to research. Once they are researching, they are completely into the learning.

    My boys built a small 9­hole golf course next to our driveway one day. It was a great product of science. They dug out the holes and channels to guide the golf ball. They played with architecture(建筑学)with a series of pipes they had found in the garage. They tested speed and momentum(动量)by creating one of the holes across the driveway. They experienced biology when deciding which front yard plants could be used as a part of the course and which needed to be pulled up.

    If I had sent them out to the yard to build a 9­hole golf course, it would have never happened. It was because it was their idea that it worked. I try to tell them some of the concepts after the fact. When they ask about something, I try to relate it back to something they have built, experienced, or felt. I try to give them a vocabulary around what they already know.

    An afternoon can change the way kids look at the world. Not bad for a day of play.

    Many of us have reached in our pockets, feeling a vibration (振动), wrongly believing our mobile phones have just rung. The phenomenon even has a name: phantom (幻觉的) vibration syndrome—and found it is surprisingly common.

    Now scientists believe that we are so alert (警觉) for phone calls and messages we are misinterpreting slight muscle spasms (痉挛)as proof of a call. Robert Rosenberger, an assistant professor at the Georgia Tech Institute of Technology has studied the delusional calls. He said sufferers describe a vague tingling feeling which they think is their mobile phone indicating it has received a text message or call while on 'silent'. But when the device is retrieved, there was no one on the other end.

    Dr. Rosenberger said he found so many people say, "This happens to me, but I thought I was the only one. I thought I was odd." It seems that the syndrome particularly affects people at the beck and call of mobile phones or pagers. A 2010 study by Michael Rothberg and colleagues found that nearly 70 per cent of doctors at a hospital in Massachusetts suffered phantom vibrations. A more recent study of US college students found the figure was as high as 90 per cent.

    While the odd feeling is widespread, it does not seem to be considered a grave problem. Dr. Rosenberger said: "It's not actually a syndrome in a technical sense. That's just the name that's got stuck to it." He added," Only 2 per cent of people consider it a problem."

    While this phenomenon is widespread, the scientific community has not yet invested much effort in getting to the bottom of why we suffer phantom calls.

    Dr. Rosenberger said: "People are guessing it has something to do with nervous energy. The cognitive(认知的)scientists are talking about brain chemistry, cognitive pathways changing. But it's not like they have brain scans to go on." He said: "We have a phone call in our pocket all the time and it becomes sort of an extension of ourselves. We have this sort of readiness to experience a call. We feel something and we think, OK, that could be a call."

There are many great GPS watches for you on the market. Now I'd like to recommend four such watches to you.

Polar Grit X Pro

Sapphire glass, which is tough and scratch- resistant, is typically an add-on or upgrade feature, so you'll be glad to know that the Polar Grit X Pro comes with this durable screen material. On top of that, Polar claims that the watch will withstand temperatures of -68 degrees up to 122 degrees F so you can stay connected on hikes in even the most extreme places in the world.

Price: $500

Amazfit GTR 3 Pro

If you want a watch to double as your fitness tracker and everyday watch, the Amazfit GTR 3 Pro is a good bet. It has 150+ sports modes. It pairs with your Alexa device, can make Bluetooth phone calls, has navigation, and tracks health measures like blood oxygen and stress levels, heart rate, and menstrual cycles.

Price: $230

Fitbit Charge 5

The Fitbit Charge 5 is perfect for those who only need a GPS watch to track basic fitness activities and personal health features like stress, heart health, sleep, and oxygen saturation. The price reflects that there are only 20 exercise modes and a water-resistance depth of 50 meters.

Price: $150

SkyCaddie LX5

This Bluetoothand Wi-Fi-enabled watch comes with 35,000 pre-loaded SkyGolf maps of golf courses worldwide, allowing you to reference the most detailed map of a golf course while you play.

Price: $300