Nowadays people are facing lots of threats（威胁）all over the world.

   A serious threat to farmers in many parts of the world is erosion（侵蚀）.Erosion happens if a large area of land is cleared of trees and is then badly treated by the farmers.The rain and winds may gradually wash away,or blow away much of the topsoil.When this happens,crops of wheat and corn become weaker and weaker until nothing grows well.If erosion continues,it will turn good land into a desert.

    In the past,when erosion appeared,farmers sometimes moved to a new place to farm.Sometimes they could not move,but continued to try to grow food in the unhealthy soil.This caused them to sink into poverty.Soon some people realized that there was little rich,fertile soil in the world.The government began to try to stop erosion.

    One of the first experiments to stop erosion began in the United States in 1933.The experiment was carried out in the area of the Tennessee River.Flood and bad farming in this area had ruined the land that had once been rich.As a result,most of the people living around the Tennessee River were very poor.

The government built big dams across the river and stored the water for use during the dry season,when there was no rain.The government workers also helped the farmers fertilize their soil and to learn new farming methods which could stop erosion.

    In the beginning,the farmers were not interested.But soon,good healthy crops began to appear on the land where new methods were used.Ten years after that the crops were extremely good.The great success of this experiment led to similar projects in other parts of the world.

With the development of science and technology,people are trying to get rid of all the threats they are facing. However,it's not an easy job,because at the same time people are polluting their homeland.

阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项。

    There are many useful suggestions that can help one to improve English. Here are some of them to increase one's English language vocabulary.

    Learning English vocabulary is about much more than just learning the right words. It is based on understanding important words and expressions.

    Learning a word will not help very much if you quickly forget it. Researches show that it takes from 10 to 20 repetitions(重复) to really make a word part of your vocabulary. Since most words are learned from how they are used in context (上下文), the more words one is shown, the better vocabulary one will have. Keep a piece of paper close to you. When you read, pay close attention to the word you do not know, write the word down and try to understand its meaning from the context. Then look up the word in a dictionary. 

    Remember that if you do not use English words that you have just learned in conversation or writing, you will forget them very quickly. So the best way to learn new words effectively is just by trying to use them in conversation and writing. Remember also that practice is the key to fluent spoken English.

    Building vocabulary is a life-long task. Remember: ＂In the beginning was the word.＂ Your future could depend on how rich your vocabulary is. It will also determine the quality of your communication.

    As countless unmade beds and unfinished homework assignments prove, kids need rules. Yet how parents make demands can powerfully influence a child's social skills, psychologists at the University of Virginia recently found after the conclusion of a study investigating the transition from adolescence to adulthood.

    Initially 184 13-year-olds filled out multiple surveys, including one to assess how often their parents employed psychologically controlling strategies, such as inducing guilt or threatening to withdraw affection. The kids rated, for example, how typical it would be for Dad to suggest that “if I really cared for him, I would not do things that caused him to worry”or for Mom to become “less friendly when I did not see things her way.”

    The researchers followed up with the subjects at ages 18 and 21, asking the young adults to bring along a close friend and, later, a romantic partner if they had one. These pairs were asked to answer hypothetical (假设的) questions that were purposefully written to inspire a difference of opinion. “We wanted to see whether they could navigate a disagreement in a healthy way, ”says study leader Barbara Oudekerk, now at the U. S. Department of Justice's bureau of statistics.

    In the October issue of Child Development, Oudekerk and her colleagues report that the 13-year-olds who had highly controlling parents struggled in friendly disagreements at age 18. They had difficulty stating their opinions in a confident, reasoned manner in comparison to the kids without controlling parents. And when they did speak up, they often failed to express themselves in warm and productive ways.

    The researchers suspect that pushy parents ruin their child's ability to learn how to argue his or her own viewpoint in other relationships. Although parents do need to set boundaries, domineering strategies imply that any disagreement will damage the bond itself. Separate findings suggest that parents who explain the reasons behind their rules and turn disagreements into conversations leave youngsters better prepared for future arguments.

    The consequences of tense or domineering relationships appear to get worse with time. This study also found that social difficulties at 18 predicted even poorer communication abilities at age 21. Psychologist Shmuel Shulman of Bar-Ilan University in Israel, who did not participate in the work, thinks these conclusions convincingly reveal how relationship patterns “carry forward” into new friendships.

    A major source of teen stress is school exams, and test anxiety is not uncommon. When you recognize your teen is under stress, how can parents help your teen stay calm before an exam?

    Be involved. Parents need to be involved in their teen's work. {#blank#}1{#/blank#}What they look for is your presence - to talk, to cry, or simply to sit with them quietly. Communicate openly with your teen. Encourage your teen to express his worries and fears, but don't let them focus on those fears.

    Help them get organized. {#blank#}2{#/blank#}Together, you and your teen can work out a time-table in which she can study for what she knows will be on the test.

    Provide a calm setting. Help your teen set up a quiet place to study and protect his privacy. Give them a nutritious diet. It's important for your teen to eat a healthy, balanced diet during exam times to focus and do her best. {#blank#}3{#/blank#}If this happens, encourage your teen to eat light meals or sandwiches. A healthy diet, rather than junk food, is best for reducing stress.

    {#blank#}4{#/blank#}Persuade your teenager to get some sleep and/or do something active when she needs a real break from studying. Making time for relaxation, fun, and exercise are all important in reducing stress. Help your teen balance her time so that she will feel comfortable taking time out from studying to spend time with friends or rest.

    Show a positive attitude. {#blank#}5{#/blank#}Your panic, anxiety and blame contribute to your teen's pressure. Make your teen feel accepted and valued for her efforts. Most importantly, reassure your teen that things will be all right, no matter what the results are.

A. A parent's attitude will dictate their teen's emotions.

B. Exam stress can make some teens lose their appetite.

C. They will only make the situation worse.

D. Encourage your teen to relax.

E. Help your teen think about what she has to study and plan accordingly

F. The best thing is simply to listen.

G. Your teen may also make negative comments about themselves.

    China has announced it's abolishing its one-child policy. What difference has it made, statistically speaking?

    400 million births prevented. The one-child policy, officially in place since 1979, has prevented 400 million births. Parents have faced fines and other punishments for having more children.

    The majority of the decrease in China's fertility(生育)rate happened in the 1970s.It dropped from 5.8 children per woman in 1970 to 2.7 in 1978. Despite the one-child policy the rate had only fallen to 1.7 by 2013. 21:28 baby death rate. Since the one-child policy was introduced, baby girls have become more likely to die than boys.

    In the 1970s, according to the United Nations, 60 males per 1,000 live births died under the age of one. For girls the figure was 53. In the 1980s, after the one-child policy became official, the rate for both was 36. By the 1990s, 26 males per 1,000 live births died before the age of one-and 33 girls. The 2000s saw 21 boys per 1,000 live births dying and 28 girls.

    1.16 boys born for every girl

    Sexually selective abortions have been considered as a major cause of China's unusual sexual imbalance.

    Gietel-Basten, associate professor in social policy at Oxford University, says the births of many girls are not registered if parents have broken the rule by having two children, adding officials often turn a blind eye. It's estimated there are now 33 million more men than women in China.

    4：2：1 families

    With the ageing of China's population and the continuation of the one-child policy, a “4: 2 :1”home is the description given to households in which there are four grandparents cared for by two working age parents, who themselves have one child.

    By 2050, it's predicted that a quarter of China's population will be 65 or older. The predicted decline in the number of people of working age is thought to have persuaded the government to drop the one-child policy.

    How much do you know about colors? The colors that you select create a distinct atmosphere in the room. {#blank#}1{#/blank#}

    Pick the color for your room and you can create whatever you feel like. The color will also help you to enlarge the space or making it more inviting, which will also make differently all about it.

However, the trick is to select the right version of that particular color. There are different hues (色调) for blues, for instance. {#blank#}2{#/blank#} Here we have presented a guide that will let you gain a deep insight about the colors.

    Blue

    {#blank#}3{#/blank#} For kitchen, bathrooms and bedrooms it is an ideal choice. Of course it is also associated with sadness that means it may not strike note for each and everyone. It is a popular choice among people. Blue comes from the cold side of the color wheel, so it can make the room feel cold, unless and until it is south filling space. If you are attracted to blue color, think of going for purple, or mix red and purple.

    Dark blue is best for a living room. Probably it is best reserved for high ceiling space. {#blank#}4{#/blank#}

    Green

    Like blue, green is also a calm shade. {#blank#}5{#/blank#} It is the shade that reflects nature and renewal. Green produces a positive energy without the feeling of overstimulation.

A. Colors can light up the mood of the room.

B. You can use it for a living room or a bedroom.

C. They won't create similar effect and atmosphere generally.

D. Traditionally, blue is just related to calmness and comfort.

E. It is better that you select colors that are very warm like blue.

F. Dark blue will really make you feel the wall appear near to you.

G. But before diving into any decision, here's what you need to know.