Last summer I sat at a long picnic table near a breathtaking mountain. While the parents were eating dinner, the kids ran up a trail in search of a secret fort. Twenty minutes later one excited little boy, James, interrupted the adult conversation.

    “Mom, Mom, you can't believe what we found!”

    Lovingly, his mother smiled and whispered, “I can't wait to hear, James, but grown-ups are talking, and there will be a pause in the conversation. Please wait for the pause.”

    On my other side, another boy came running up to his mother with equal enthusiasm.

    “Mom, Mom, we had so much fun—”

    “I am talking! Don't interrupt,” she said.

    “But, Mom—”

    “Be quiet! Can't you see that I am talking?”

    “But Mom we found the—”

    “Shut up, Steve!” she yelled.

    My heart sank. I knew what was coming. James, on my right, patiently waited for the pause, enthusiasm still alive and well. Steve, on my left, walked away from the table, looking shamed, carrying with him stories of secret forts never to be shared.

    What markedly different messages to the child! “Wait for the pause” versus “Shut up” gets incorporated (包含)so differently into a child's developing sense of self.

    Harsh(刺耳的) words have bad effects. That's why I want you to promise to delete the phrases “Shame on you” or “You should be ashamed” from your vocabulary. I have seen countless patients whose parents' thoughtless words echoed in their heads and chipped(消除) away at their self-worth, even decades later.

    So we have to discipline ourselves to make our instructions constructive. One great tool is to look for positive behavior to reinforce. Don't ignore the things that your kids are doing right. Thank your children. Tell them that you noticed how they waited patiently or cleared their plate without being asked. Chances are that they will do it again. Let them feel noticed, appreciated, and valued. There's no better way to shape behavior.

    Tattoos (纹身) are becoming more and more common. But they are not a new thing. Scientists have found some frozen bodies from around 3,000 BC and their skin shows the marks of tattoos. For example, Otzi, the Iceman (the oldest body ever found), was discovered in the mountains of Austria. He had many different lines and crosses tattooed on his back and his knees.

    The most common places to get tattoos are the tops of the arms for men and the bottoms of the backs for women. Any mark can be used but there are some common ideas. Some people like to get animals, like dragons, birds and tigers. Other people like to get something written in a foreign language, so Chinese and Japanese words are common in America and the UK. If you can't read the language, make sure you get someone to check what they represent because the tattoo artist could write anything and you would never know.

    It is a big decision to get a tattoo because they are very difficult to remove. It is possible with expensive laser surgery (激光手术) but this is very painful and amazingly expensive and the skin will never be perfect afterwards. You want to do a test, to see how you look with a tattoo, you can get a temporary tattoo which disappears after about a month. This kind is very popular in India, where people often have them for festivals.

    In some countries, such as Japan and Korea, tattoos are still connected with law-breaking activities and it isn't normal to see a tattoo in public. In many places of Europe and America, most people don't care very much whether you have a tattoo or not, though there are some types of job where they don't like tattoos. But some Presidents of the USA have had them.

    After decades of cat-and-mouse between athletes and the word anti-doping agency (WADA), athletes found what they must have believed to be the ultimate (终极的) doping agent: their own blood. To enhance athletic performance with your own blood, you draw your blood and store it in a freezer. Your body compensates by creating more blood. Then, months later, just before a competition, you can re-inject (注射) the old blood for a boost. As the red-blood-cell count goes up, so does an athlete's ability to absorb oxygen. The more oxygen you get with each breath, the more energy your body is able to bum and the better you are able to perform.

    Although the enhancement is small compared to actual drugs, it can be the difference between a gold medal and a silver medal. Best of all, "extra blood" was never something WADA tested for.

    But WADA wasn't going to sit by and be fooled. What it came up with in response might be a solution to stop doping once and for all: an athlete biological passport (ABP). The idea is to record some biological features of an athlete through testing done at regular intervals. The biological passport's partial implementation (实施)—recording blood and steroid levels—began in January 2014.

    When all necessary biological features are finally combined, WADA will no longer need to worry about finding new methods to detect a drug. It will only have to detect (检测) resulting changes in the body. In the case of blood doping, if the athlete's normal red-blood-cell count is, say, 47%, but then is found to be 51% after a competition, cheating may have been involved.

    WADA is confident that the biological passport could even prevent genetic changes—the ultimate, ever-lasting enhancement—which are surely coming next. If an athlete inserts a performance enhancing gene, it will probably leave detectable changes in the body, that would differ from the athlete's feature in the biological passport.

    In today's society, language plays a key role in defining gender (性别) by vocabulary, and also their non-verbal (非语言的) vocabulary. Each one of these different types of ways of communicating is obviously different between men and women.

    Many different studies show that men tend to talk much more than women. It has also been proven that women tend to speak faster than men; this is due to the fact that women tend to be interrupted more often than men are, and also have the ability to speak more clearly, precisely, and more quickly than men. In one study it was found that women spoke for an average of three minutes describing a painting, as opposed to the thirteen-minute average it took men to describe it.

    Men and women also tend to have a very different non-verbal way of communicating, which can also make it very hard for one another to understand what the opposite sex is trying to say. Men's body language is much more reserved when talking to women. Men tend not to make as much eye contact and they generally stay farther away from women when talking to them. Men avoid other people's body space while talking, and they also tend to sit back when talking. All of these have given off the impression of disinterest or boredom. Women are by far better listeners and much more enjoyable to talk with and they tend to raise more topics for conversation.

    Women also make it clearer whether or not the conversation is going somewhere or just stuck in neutral. After learning about our styles of communicating with each other, I have decided that although men have not quite mastered communicating, what fun would it be if we all spoke the same "language"? The little games men and women play with each other while conversing would be lost. The question everyone asks himself or herself after talking with someone of the opposite sex, "I wonder if there's something there?" would no longer exist.

    The fiddler crab (蟹) is a living clock. It indicates the time of day by the colour of its skin, which is dark by day and pale by night. The crabs changing colour follows a regular twenty-four hour plan that exactly matches the daily rhythm (节奏) of the sun.

    Does the crab actually keep time, or does its skin simply answer to the sun's rays, changing colour according to the amount of light strikes it? To find out, biologists kept crabs in a dark room for two months. Even without daylight, the crab's skin colour continued to change exactly on time.

    This characteristic(特性) probably developed gradually in answer to the daily rising and setting of the sun, to help protect the crab from sunlight and enemies. After millions of years it has become completely regulated (受控制) inside the living body of the crab.

    The biologists noticed that once each day the colour of the fiddler crab is especially dark, and that each day this happens fifty minutes later than on the day before. From this they discovered that each crab follows not only the rhythm of the sun but also that of the tides (潮水). The crabs period of greatest darkening is exactly the time of low tide on the beach where it was cought!

You already know that playing sports helps keep you fit. But you might not know why it's so important to get a sports physical at the beginning of your sports season.

{#blank#}1{#/blank#} Most require students have a sports physical before they can play school sports. But even if a sports physical isn't required, doctors still recommend getting one if you are active in any sports.

A sports physical can help find out and deal with health problems that might affect your sports performance or increase the chance of getting hurt. For example, if you have frequent asthma (哮喘) attacks, the doctor can change your medicines. {#blank#}2{#/blank#} Your doctor may offer training tips or recommend exercises or physical therapy (疗法) to help you avoid injuries.

Most teens go to their regular doctor's office to get a sports physical, since your doctor knows you and your health history best. Some get their sports physical at school. {#blank#}3{#/blank#} Each one is armed with a medical professional who does a specific part of the physical exam.

Plan your sports physical at least 6 weeks before your sports season starts. {#blank#}4{#/blank#} Neither you nor your doctor will be very happy if your sports physical is the day before baseball practice starts and it turns out there's something that needs to be taken care of before you can suit up.

Sports physicals are usually good for 1 year, though you probably will have to complete a sports form each season. If there are any changes in your health history, like a new injury or you notice new symptoms (症状), you may need to see the doctor before being allowed to play. {#blank#}5{#/blank#}.

A. That way, you can breathe more easily when you run.

B. Let your gym teacher or coach know if your health has changed.

C. During school physicals, you may go to "stations" set up in the gym.

D. The medical history questions are usually on a form that you can bring home.

E. Mention you need a sports physical so your doctor can set aside time to do both.

F. The sports history and exam help to tell if it's safe for you to take part in your sport.

G. If your doctor finds a problem, this should leave enough time to for tests or treatment.