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    Anyone who has ever tried to stop smoking knows how difficult it is to quit. There is no lack of information about how unhealthy smoking is for you- not to mention the unpleasant smell. So why would teens ever begin to smoke?

    {#blank#}1{#/blank#} Research shows that the majority of smokers lit up their first cigarette in their early or mid-teens, precisely at a time when children are beginning to establish their own identity apart from their parents. Smoking can be an act of rebellion(反抗) against parents or authority figures, as well as a way to fit in with others and feel accepted.

    Here are some things that parents can do to help a child stay smoke-free.

    Start talking to your teen about how bad smoking is for him early, well before his teens. Keep talking, too. {#blank#}2{#/blank#}

    {#blank#}3{#/blank#} For example, smoking makes your hair and clothing smell bad, stains the teeth, and reduces your lung power to play sports.

    {#blank#}4{#/blank#} Talk about the addictive power of smoking and tell him while those few cigarettes are his choice, the addiction that occurs shortly afterwards makes him powerless to decide whether or not he wants to light up.

    Work on self-esteem(自尊) and self-confident with your teen. Much of the attraction of smoking is to gain acceptance. {#blank#}5{#/blank#}

    On Monday, the Centers for Disease Control and Prevention predicted that 42% of Americans could be overweight by 2030. Our expanding waistlines lead to not only a medical problem, but according to a recent article In The New York Times, it could also endanger personal safety in some situations—in an airplane crash, for example.

    The New York Times' Christen Negroni reports that engineers and scientists are questioning whether airplane seats are adequately constructed to protect overweight travelers. Government standards for airplane seat strength（强度）— first set moe than 60 years ago — require that the seats be made for a passenger weighing 170 pounds (77kg). Today, the average American man weighs nearly 194 pounds (88kg) and the average woman 165 pounds (75kg). Negroni reports:

    “If a heavier person completely fills seat, the seat is not likely to behave as intended during a crash,” said Robert Salazar, the leading scientist at the Center for Applied Biomechanics at the University of Virginia. “The energy absorption that is built into the aircraft seat is likely to be overpowered and the passengers will not be protected properly.”

    “Nor would the injury be limited to that passenger only,” Dr. Salzar said. “If a seat or a seat belt fails,” he said, “those people who are seated nearby could be endangered from ‘the uncontrolled movements of the passenger'.”

    Most complaints about airplane seats focus on their lack of comfort and high ticket price, and whether overweight passengers should be made to buy two seats. But The New York Times' article brings up another reason to feel anxious about flying. Investigators of the issue got in touch with the airplane seat and seat belt makers, but they refused to comment on the problem. Experts agreed that crash testing should be done with overweight dummies （人体模型）. Both airplane seats and seat belts should be tested, they said.

    Fortunately, however, according to Nora Marshall, a senior adviser at the National Transportation Safety Board, the board's investigators have never seen an accident involving a commercial plane in which the weight of a passenger was a problem.

    In our daily life, it is necessary to make small talk in some situations. It helps to fill time between people when it is very quiet. You may not feel like talking with someone else or you are very shy at the beginning, but it is sometimes thought to be not polite to say nothing.

    People use small talk almost every day. It usually takes place when you meet someone you don't know at all or someone you're not familiar with. For example, waiters and hairdressers often make small talk with their customers（顾客）. If you happen to be outside when the postman comes to your door, you might make small talk with him, too.

    Most often, small talk happens in places where people are waiting for something. For example, you might talk with another person who is waiting for the bus to arrive. People also make small talk in a doctor's waiting room, or when they are waiting in a line to buy something. At the office, people make small talk in lunch rooms, especially if there is a line-up. Mingling is often required（要求）among people who don't know each other very well at a party. That is to say, they are expected to walk around and talk with others.

    The most common time for small talk to happen is the first time you see or meet someone on a given day. For example, if you see a neighbor in the waiting room of the airport you might say hello and discuss the sports or weather. However, the next time you see each other you might just smile and say nothing. If there is very little noise, it might be the right time to start a pleasant conversation. If someone is reading a book at the bus stop, it is probably not a good idea to start a conversation. Another good time to make small talk is during a break in a meeting when there is nothing important going on. However, it is important to recognize the signal when the other person wants the conversation to stop.

    Gardening is a very popular hobby. And it is one that produces wonderful results – food for your dinner table and flowers for your home! Gardens themselves can be very beautiful. So you would think that a garden path is a great place to be. Well, in conversation, it is not. Leading someone up the garden path means you are trying to trick them. You are not trying to show them your beautiful flowers.

    Speaking of beautiful flowers, gardeners love to see small buds (芽) forming on their plants. Besides plants and flowers, people can bud, too. If a child is good at drawing and painting, we can call him a budding artist. So “budding” describes something that is beginning to develop.

    On the opposite end, you stop something from growing if you nip it in the bud. This is a common expression when we talk about stopping something bad and preventing it from continuing. It's good to nip small problems in the bud before they turn into big problems.

    Now flowers that bloom （开花）are beautiful to see – even garden-variety flowers. “Garden-variety” describes anything that is common and not so special. You can have a garden-variety cold—not a serious illness.

    Now, a problem that many gardeners have is weeds. Weeds grow easily and can quickly take over a garden. In conversation, we sometimes use “weeds” to mean too many details. So, if you are in the weeds, you are taken over by too many details.

    As we said, weeds grow quickly. So do children. So, we like to say a child grows like a weed. This expression compares a child's fast growth to that of a weed.

    The Secretary-General of the U.N. has always been chosen in private meetings. But for the first time in its 70-year history, part of the selection process is taking place in public.

    At least eight countries have announced their candidates (候选人) for the position, among whom are women, including Irina Bukova from Bulgaria, Susana Malcorra from Argentina and Helen Clark from New Zealand. 56 countries says the next U.N. chief should be a woman. There have been eight U.N. chiefs, none of whom was a woman.

    All member states were permitted to ask the candidates questions during two hour-long meetings last week in the U.N. General Assembly (联合国大会). The candidates were also asked some of the 1,000 questions written by people on social media.

    They were asked questions about development, how they would improve efforts to create peace and how they would protect human rights.

    The U.N. Security Council will examine the candidates' backgrounds. Then the 15 members will vote secretly until one person is chosen. The General Assembly will then vote on whether to accept the choice.

    Britain, China, France, Russia and the United States are the five permanent members of the Security Council. Experts say they are likely to have more influence on who will be the new secretary-general than the 10 non-permanent nations on the council.

    The Security Council will begin to discuss who will be named the next secretary-general in July. A new secretary-general may not be confirmed until as late as November.

    The U.N. has a tradition of choosing its new leader from a part of the world different from its current leader. U.N. Secretary-General Ban Ki-moon is from Asia. The previous U.N. chief was Kofi Annan, who was from Africa.

    Dan Thomas is a spokesman for the president of the General Assembly. He says there is no rule that says where a new secretary-general must come from. But most observers say the new U.N. chief will not be from Asia or Africa.

Biofuels (生物燃料), gained from plants and animal matter, are a key solution to the environmental problems caused by fuels like coal. "Bioalcohol (生物酒精) is the most common biofuel and is produced by sugars found in materials such as corn. With some engine redesigned, it can be used directly by cars, buses, etc. ," says Professor Daniel Tan, "12 percent of transport fuel could come from biofuels, especially bioalcohol, by 2030. "

But a 2016 study of biofuels said, "Bioalcohol presently is mostly produced with food crops. Altogether, the environmentally-friendly biofuels rely on about 2-3 percent of the global water and land used for agriculture, which could feed a large number of hungry people. "

Energy experts have therefore been trying to deal with the problem. Recent research led by an international team found that the agave (龙舌兰) plant might offer a way out. This plant tends to be the right bioalcohol source to supersede others such as sugarcane (甘蔗) and corn.

Daniel Tan explains that the agave can be grown in unfavorable conditions and is not a major food crop. "It can grow in areas that lack water and rainfall without being watered by farmers, and it does not compete with food crops or put demands on limited water. This kind of useful plant is recently being grown in Australia. It can survive Australia's hot summers," he says.

The study finds that sugarcane produces just a little more fuel per square meter each year than the agave. However, the agave outperforms sugarcane in a range of areas, including pollution to the earth, and water using. The agave uses 69 percent less water than sugarcane and 46 percent less water than corn for the same amount of fuel produced. As for corn，it produces less fuel per square meter each year than the agave.

However, Daniel Tan states: "The first generation of bioalcohol from the agave recently faces a big competition from oil, whose recent low price makes it far more attractive to customers. Without some policy support from the government, bioalcohol production from the agave faces big challenges. "