Modern man has cleared the forests for farmland and for wood, and has also carelessly burned them. More than that, though, he has also interfered(干预) with the invisible bonds between the living things in the forests. There are many examples of this kind of destruction. The harmfulness of man's interference can be seen in what happened many years ago in the forest of the Kaibab plateau （凯亚巴布高原） of northern Arizona. Man tried to improve on the natural web of forest life and destroyed it instead.

    The Kaibab had a storybook forest of large-sized pine, Douglas fir, white fir, blue and Engelmann spruce. In 1882 a visitor noted, "We, who have wandered through its forests and parks, have come to regard it as the most enchanting（迷人的）region it has ever been our privilege to visit. "This was also the living place of the Rocky Mountain mule deer. Indians hunted there every autumn to gather meat and skins. The forest also had mountain lions, timber wolves and bobcats that kept the deer from multiplying too rapidly.

    Then, in 1906, President Theodore Roosevelt made the Kaibab a national game preserve. Deer hunting was forbidden. Government hunters started killing off the deer's enemies. In 25 years' time, 6,250 mountain lions, wolves and bobcats were killed. Before the program, there were about 4,000 deer in the Kaibab, by 1924, there were about 100,000.

    The deer ate every leaf and twig they could reach. But there was not nearly enough food. Hunting of deer was permitted again. This caused a slight decrease in the deer herd，but a far greater loss resulted from starvation and disease. Some 60 percent of the deer herd died in two winters. By 1930 the herd had dropped to 20,000 animals. By 1942 it was down to 8,000.

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    Your glasses may someday replace your smartphone, and some New Yorkers are ready for the switch. Some in the city can't wait to try them on and use the maps and GPS that the futuristic eyewear is likely to include.

     “ I'd use it if I were hanging out with friends at 3 a. m. and going to the [bar and wanted to see what was open,” said Walter Choo, 40, of Fort Greene.

      The smartphone-like glasses will likely come out this year and cost between $250 and $600, the Times said, possibly including a variation of augmented(增强的) reality, a technology already available on smartphones and tablets (平板电脑) that overlays information onto the screen about one's surroundings. So, for example, if you were walking down a street, indicators would pop up showing you the nearest coffee shop or directions could be plotted out and come into view right on the sidewalk in front of you.

     “ As far as a mainstream consumer product, this just isn't something anybody needs,” said Sam Biddle, who writes for Gizmodo.com.  “ We're accustomed to having one thing in our pocket to do all these things,” he added, “and the average consumer isn't gonna be able to afford another device (装置) that's hundreds and hundreds of dollars.”

    9to5Google publisher Seth Weintraub, who has been reporting on the smartphone-like glasses since late last year, said he is confident that this type of wearable device will eventually be as common as smartphones.

     “It's just like smartphones 10 years ago,” Weintraub said. “A few people started getting emails on their phones, and people thought that was crazy. Same kind of thing. We see people bending their heads to look at their smartphones, and it's unnatural,” he said. “ There's gonna be improvements to that, and this a step there.”

The Secret of a Long Life

    I am Peter Brown. I am a writer with an important magazine. The other day I saw a white-haired man sitting on the chair in front of his house. I could see the wrinkles (皱纹) in his face and neck, and his wrinkled hands. Articles on the secrets of living to an old age are always popular with our readers, so I decided to write a story and discover the secret of this man's long life. As I went near him, I said:

    “Sir, would it be okay if I talked with you for just a moment?”

    “Not at all. Actually, it would make me very happy. I get very bored sitting here, even for a short time. Until a little while ago, I lived a full and active life without a moment's rest.”

    “Well, they say that a lot of activities help one to live a long time.”

    “That's true, very true. I still feel very well, although my step has slowed down a little.”

    The conversation continued in that way for a while. Although I tried to be very thoughtful about getting information from older people, it seemed to me that it would now be all right to begin to ask some polite questions.

    “Would it be okay if I smoked?”

    “Not at all.”

    “I'd offer you one, but I suppose you probably don't smoke, or drink, or…”

    “You're wrong! I've always smoked a great deal. And until a little while ago, I went dancing every night. And as for alcoholic drinks ...”

    “Do you mean to say that you've done these things all your life?”

    “Of course. Why does that surprise you so much?”

    “I've always been told that doing those things is bad for the health.”

    “Nonsense!”

    “I suppose that you have another secret ... a lot of fruit... vegetables ... a lot of exercise in the fresh air…”

    “Don't be silly! I hate exercise in the fresh air, and I don't like any kind of vegetable.”

    “This is unbelievable!”

    “What do you mean, unbelievable? What are you talking about?”

    “It's just that I can't understand how you've been able to live like that and to have lasted so long. Tell me, how old are you?”

    “Me? I'm twenty-eight. Why?”

    Rent control, like all other government-mandated（强制执行的）PRICE CONTROL,is a law placing a maximum price, or a "rent ceiling," on what landlords may charge tenants（房客）.It is a program designed to stop rents from rising rapidly and is used mainly in large urban areas where there are more people than housing. In cities with rent control, the city government sets the maximum rent that a landlord can charge for an apartment. Supporters of rent control argue that it protects people who are living in the apartments. Their rent cannot increase; therefore, they are not in danger of losing their homes. However, almost all the critics conclude that rent control is destructive. They say after a long time, rent control may have negative effects.

    In a 1990 survey of 464 people published in the May 1992 issue of the American Economic Review,93% of US respondents agreed that a ceiling on rents reduces the quantity and quality of apartments available. Landlords are too cautious (perhaps too smart) to put their faith in rental apartments because they know that the rental-controlled apartments cannot increase their profits. Therefore, they invest in other businesses where they can increase their profits. They do not invest in new buildings which would also be rent-controlled. As a result, new apartments are not built. Many people who need apartments cannot find any.

    Some theorists argue that the minimum wage law can cause problems in the same way. The federal government sets the minimum that an employer must pay workers. The minimum helps people who generally look for unskilled, low-paying jobs. However, if the minimum is high, employers may hire fewer workers. They will replace workers with machinery. The price, which is the wage that employers must pay, increases. Therefore, other things being equal, the number of workers that employers want decreases. Thus, critics claim, an increase in the minimum wage may cause unemployment. Some poor people may find themselves without jobs instead of with jobs at the minimum wage.

    Supporters of the minimum wage say that it helps people keep their dignity, Because of the law, workers cannot sell their services for less than the minimum. Furthermore, employers cannot force workers to accept jobs at unfair wages.But the supporters make a big error. They fail to realize that it is possible for such a law to increase wages beyond the value of what the workers contributes.

    Economic theories predict the results of economic decisions such as decisions about farm production, rent control, and the minimum wage. The predictions may be correct only if "other things are equal". Economists do not agree on some of the predictions. They also do not agree on the value of different decisions. Some economists support a particular decision while others criticize it. Economists do agree, however, that there are no simple answers to economic questions.

    Travel is fun and exciting, but it's not if you get sick. You may think, “Not me, I won't get sick on my vacation. ”But for many people, that is what happens.

    A vacation is supposed to be a time for relaxing. But very often it is not.  “What can I do when I am a tourist?” This is what we should often think about.  Usually there are so many places to visit： museums, shops, parks and churches. You may spend most days walking around these places. This can be very tiring. Your feet may hurt.  And you may have a terrible headache after a few hours. If this is what you feel, you should take a rest. Don't ask your body to do too much. A tired body means a weak body. And a weak body can make you get sick easily. Just sit down for a few hours in a nice spot. In good weather, look for a quiet park bench. Or you can rest at a café. You can learn a lot by watching people when you have a rest.

    Sleep is also important. If you want to stay healthy you need enough sleep.  You may have trouble sleeping at night when you travel. Your hotel room may be noisy, or the bed may be uncomfortable.  If that is true, don't be afraid to change rooms or hotels. You may not get enough sleep for another reason. You may want to stay out late at night. In many cities the night life can be very exciting. Then you should plan to sleep for an hour during the day. That extra hour can make a big difference.

    Finally, if you want to stay healthy, you must eat well. That means eating the right kinds of foods. Your body needs fresh fruit and vegetables, and some meat, milk or cheese. When you are in a new country you may want to try new foods but you need to be careful about how much you eat. Lots of rich food is not very good for you.

    It started during a yoga class. She felt a strange pull on her neck, a feeling completely foreign to her. Her friend suggested she rush to the emergency room. It turned out that she was having a heart attack.

    She didn't share similar symptoms with someone who was likely to have a heart attack. She exercised, watched her plate and did not smoke. But on reviewing her medical history, I found that her cholesterol (胆固醇) level was sky-high. She had been prescribed a cholesterol-lowering statin (他汀) medication, but she never picked up the prescription because of the scary things she had read about statins on the Internet. She was the victim of fake medical news.

    While misinformation has been the object of great attention in politics, medical misinformation might lead to an increase in deaths. As is true with fake news in general, medical lies tend to spread further than truths on the Internet—and they have very real bad consequences.

    False medical information can also lead to patients experiencing greater side effects through the "nocebo effect (反安慰剂效应) ". Sometimes patients benefit from an intervention (干预) simply because they believe they will—that's the placebo effect (安慰剂效应). The nocebo effect is the opposite. Patients can experience harmful effects because they anticipate them. This is very true of statins. In blinded trials, patients who get statins are no more likely to report feeling muscle aches than patients who get a placebo. Yet, in clinical practice, according to one study, almost a fifth of patients taking statins report side effects, leading many to discontinue the drugs.

    What else is on the fake news hit list? As always, vaccines (疫苗) . False concerns that the vaccine may cause side effects have greatly reduced coverage rates.

    Cancer is another big target for pushers of medical misinformation—many of whom refuse alternative therapies. "Though most people think cancer tumors are bad, they're actually the way your body attempts to contain the harmful cells," one fake news story reads. It warns that prescription medications lead to the uncontrolled cell mutations (变异) .

    Silicon Valley needs to face this problem. I am not a free-speech lawyer, but when human health is at risk, perhaps search engines, social media platforms and websites should be held responsible for promoting or hosting fake information. Meanwhile, journalists should do a better job of spreading accurate information.