Winters are long and unforgiving in North Dakota. The winter of 1996 was especially brutal. It was a hard time in my own life too. A neck injury had kept me flat in bed for nearly a year. “Just in time for Easter,”my husband, Dick, said. But how could I feel the joy when the snow was four feet deep and I had months of painful physical treatment ahead?

    I was doing the dishes one day, feeling hopeless when there was a tap against the glass. It was a branch of the troublesome cottonwood (棉白杨).Back in the fall of 1979, it was a new subdivision (分支）then, an eight-foot stick. The people who'd briefly occupied the house before us had placed the pipe from the pump next to it. The earth was so wet that the poor thing had fallen down, most of its bare root system pointing skyward, and blowing hopelessly back and forth in the cold wind. Dick decided to pull it out one day, but I protested.

    “Look at how hard it's trying!” I said, pointing to the way it strongly kept hold of the earth. “It deserves a chance.”

     Dick borrowed some tools. We packed dry soil around the tree and put up some stakes (桩) into the ground, making it stand upright. That winter was still terrible. Surprisingly,in the spring my “rescue stick”put forth a few leaves,then with lots of branches. The year after that, we were able to remove the stakes. By the 1990s that little stick was a giant, towering over the house.

    Now the tapping at the window continued, louder as the wind picked up, almost as though to tell me to look up. At last, I did. I caught my breath. In the window against the icy blue sky, thousands and thousands of fresh red buds were waving in the wind.

    The tree was bursting with life and I had a wonderful Easter.

    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.

    We all need to eat. So, meals could be a chance to stop what we're doing and spend time with the people in our lives. A recent study from a team of South Korea suggests that eating together has many good effects on children and teenagers while frequently eating alone may lead to poor eating habits and poor food choices. People who eat alone more than twice a week have a greater risk of developing high blood pressure.

    There are benefits of family dinners on children and teenagers.

    In 2014, the Organization for Economic Cooperation and Development (OECD) looked at data from nearly three-quarters of the world's countries. Among its findings is the fact that students who share a main meal with their families are less likely to hate school. Children who eat a main meal with their families are also less likely to take drugs (毒品).

    In the report, titled “The Importance of Family Dinners (VIII),'' researchers say that teens who have frequent family dinners are more likely to say their parents know a lot about what's going on in their lives.

    Another study from the University of Montreal finds that children who eat with their families experience long-term physical and mental health benefits. These children are physically in better shape and drink fewer sugary soft drinks. These children also seem to have better social skills and are less violent.

    One of the researchers, Pagani, involved in this study is a professor at the university. She says that mealtimes with parents possibly provide young children with firsthand social events, which helps them have better communication skills.

    Robots make me nervous—especially the ones which seem to think for themselves. I was embarrassed to admit this till I heard that Bill Gates, the founder of Microsoft, felt the same way.

Gates said in an interview with the social networking and news website Reddit: "I am in the camp that is concerned about super intelligence. First the machines will do a lot of jobs for us and not be super intelligent．That should be positive if we manage well. A few decades after that, though, the intelligence is strong enough to be a concern."

    Well, maybe I don't have to worry about my computer and kitchen equipment yet. After I use them I can always pull the plug. But in the future, machines might find a way to prevent us from switching them off. There's a terrible thought!

    Maybe the problem with computers too clever for us is not that they are evil like some we've seen in sci-fi movies. What could put us in danger is that they might be too efficient. That's what philosopher Nick Bostrom from Oxford University believes. He says that machines are indifferent to humans and in pursuit of their own goals，the destruction of people might be just additional damage. Bostrom gives us an example: A machine which might have its only goal to produce as many paperclips as possible might look at human bodies as extra material for paperclips and go after you. Because it is, well, a machine, it would not take pity on you.

    It's a good thing that American writer Isaac Asimov thought about how far robots can go and left us his three rules of robotics. They state that a robot may not hurt a human being or allow the human being to come to harm.

I'm glad my machines at home are "dumb". All my cleaner wants to take over is the carpet in my living room. Let's hope they don't create an appliance which wants to take over the world!

    You probably know who Marie Curie was, but you may not have heard of Rachel Carson. Of the outstanding ladies listed below, who do you think was the most important woman of the past 100 years?

    Jane Addams (1860-1935)

    Anyone who has ever been helped by a social worker has Jane Addams to thank. Addams helped the poor and worked for peace. She encouraged a sense of community by creating shelters and promoting education and services for people in need. In 1931, Addams became the first American woman to win the Nobel Peace Prize.

    Sandra Day O'Connor (1930-present)

    When Sandra Day O'Connor finished third in her class at Stanford Law School, in 1952, she could not find work at a law firm because she was a woman. She became an Arizona state senator(参议 员) and ,in 1981, the first woman to join the U. S. Supreme Court (最高法院). O'Connor gave the deciding vote in many important cases during her 24 years on the top court.

    Rosa Parks (1913-2005)

    On December 1,1955, in Montgomery, Alabama, Rosa Parks would not give up her seat on a bus to a white passenger. Her simple act landed Parks in prison. But it also set off the Montgomery bus boycott (联合抵制). It lasted for more than a year, and kicked off the civil-rights movement. "The only tired I was, was tired of giving in," said Parks.

    Artificial intelligence (AI) technology may soon be a useful tool for doctors. It may help them better understand and treat diseases like breast cancer in ways that were never before possible.

    Rishi Rawat teaches AI at the University of Southern California's (USC) Clinical Science Center in Los Angeles. He is part of a team of scientists who are researching how AI and machine learning can more easily recognize cancerous growths in the breast. Rawat provides information about cancer cells to a computer. He says this data helps the machine learn." You can put the data into computers and they will learn the patterns and the pattern recognition is important to making decisions."

    David Agus is another USC researcher. He says machines are not going to take the place of doctors. "Computers will not treat patients, but they will help make certain decisions and look for things that the human brain can't recognize by itself. Once a confirmed cancerous growth is removed, doctors still have to treat the patient to reduce the risk of cancer returning. The form of treatment depends on the kind of cancer."

    Currently, researchers take a thin piece of tissue, put it on a small piece of glass and add color to better see the cells. That process could take days or even longer. Scientists say artificial intelligence can do something better than just count cells. Through machine learning, it can recognize complex patterns, or structures, and learn how the cells are organized.

    The hope is that machines will soon be able to make a quick identification of cancer that is free of human mistakes. "All of a sudden, we have the computing power to really do it in real time. We couldn't have done this, we didn't have the computing power to do this several years ago, but now it's all changed." Agus adds that the process could be done for almost no cost in the developing world. He says that having a large amount of information about patients is important for a machine to effectively do its job in medicine.

    The University of Southern California researchers are now only studying breast cancer. But doctors predict artificial intelligence will one day make a difference in all forms of cancer.