An environment that is biologically diverse has lots of different plants and animals. This is needed for people to have enough high-quality food to lead active and healthy lives. The idea of biodiversity recognizes that natural systems are complex and depend on one another. In agriculture, depending on only a few crops can be dangerous. One example is the Great Potato Famine in the eighteen forties. Ireland depended on potatoes as a food resource. But a disease ruined the crop for several years. More than one million people died from hunger. Yet experts say the world depends on only four crops to provide half its food energy from plants. These are wheat, maize, rice and potato. The experts say it is important to support a large number of different food crops and farm animals that can survive different conditions. Such diversity helps to reduce the risk from losing one main crop. Farmers also have a responsibility to protect wild species. The Food and Agriculture Organization says more than forty percent of all land is used for agriculture. Farm fields are an important place for wild animals to live and reproduce. Also, farmers must consider the effects that agriculture has on the environment. Farm pollution or poor agricultural methods can harm wetlands, rivers and other environments needed to support life. Invasive species are a severe threat to biodiversity. Plants and animals often spread without natural controls when they enter areas they are not native to. They can destroy crops, native species and property. Invasive species cost the world economy thousands of millions of dollars each year. Q13: What does this report mainly talk about? Ql4: According to experts, what are the four crops the world chiefly depends on? Q15: Why are invasive species a severe threat to biodiversity? Importance of biodiversity. Protection of wild species. Farm pollution. Agricultural methods.

W: I was always surprised to see Tom using that tape recorder you were going to throw away. M: Yes, it’s very old. That he got it to work amazes me. Q: What do we know about Tom? He fixed the tape recorder. He is still working despite his age. He is trying to fix the tape-recorder. He bought a new tape-recorder.

W: Frank is thinking of buying a car. M: Should he be doing that with all the other expenses he has? Q: What do we know about Frank? He should buy a car. He has enough money for a car. He spends money like water. He can’t afford a car.

The new school year has begun in America. But some children do not go to school. Instead, they learn at home, usually with their parents as teachers. Educational companies, libraries, school systems and the Internet provide families with teaching material. Homeschooling is increasingly popular. Homeschooling groups estimate that two-million children, around two percent, learn at home. The last government estimate was 850,000 in 1999. Current numbers are not expected until next year. Some parents choose homeschooling because of their religious beliefs. Others say it provides more time for the family to be together. Many parents also believe homeschooling avoids problems of a lot of traditional schools. One problem is classes with too many students. Critics, though, say children need to attend school with other children to help them learn things like social skills. They also say that some homeschooled children do not get a very good education. All fifty states and the District of Columbia permit homeschooling. Some, however, require more preparation by parents or testing of children than others do. There is even a National Home School Honor Society. Membership is based in part on the same tests that students take in school. Homeschooled children go to college and have also won top competitions. These include this year’s National Geographic Bee. Fourteen-year-old James Williams knew that the Indian state of Goa is a former colony of Portugal. Q10: Which of the following is true about homeschooling in America? Q11: Why do some parents choose homeschooling? Q12: What is the National Geographic Bee? 850,000 children are currently learning at home. Teaching materials are from one source only. All the states in the U.S. permit homeschooling. Homeschooled children can hardly go to college.

Experts find it hard to explain why the maternal mortality rate went up in 2015 in the United States. recovery success death development

My daughter was quite upset because a large group of undesirable strangers had spoiled her party. unwelcome generous hopeful amused

Under the leadership of Xi Jin-ping, governments at each level are bearing more responsibilities. producing harboring tolerating assuming

My roommate was already sound asleep by the time I came back to my dorm last night. audibly visually thoroughly rationally

My father used to tell us some gripping stories in winter when he was not so busy. fascinating breaking fictional redundant

About 60 percent of Libyans went to the polls to elect their representatives and then_______the streets in celebration. took up took in took on took to

If you take the right approach_______this work, you won’t go_______the wrong direction. for...to to...in in.. .for by.. .towards

Obesity has become a household word in the United States. Today, about one【C1】______ three American kids is overweight, nearly【C2】______the rate in 1963. Childhood obesity is the No. 1 health【C3】______among American parents, topping drug abuse and smoking. Obesity is among the easiest medical conditions to recognize but most difficult to treat. Unhealthy weight gain due to poor diet and lack of exercise【C4】______over 300,000 deaths annually. Obesity is causing a broad range of health problems that【C5】______weren’t seen until adulthood, including high blood pressure. There are also psychological effects: Obese children are more【C6】______to low self-esteem, negative body image and depression. They are much more likely to become overweight adults【C7】______they maintain healthier【C8】______of eating and exercise. The causes of obesity are extremely complicated. Obesity occurs when a person eats more calories than【C9】______. If one parent is obese, there is a 50 percent chance that their children will be obese.【C10】______certain medical disorders can cause obesity, less than 1 percent of all obesity arises from physical problems.

It was supposed to be a quick diversion, Katie Inman told herself last week as she flipped open her laptop. She had two tests to study for, three problem sets due, a paper to revise. But within minutes, the MIT sophomore was drawn into the depths of the Internet, her work put aside. “I had just closed Facebook, but then I reopened it. It’s horrible,“ said Inman, a mechanical engineering major. “I would type a sentence for my paper, and then get back on Facebook.“ Desperate for productivity, Inman did something many of her classmates at one of the most wired campuses would find inconceivable. She installed a program that blocks certain websites for up to 24 hours. No social networking. No e-mail. No aimless surfing. While Inman took matters into her own hands, some MIT professors are urging college leaders across the country to free students from their binding to technology. Over the past decade, schools raced to connect students to the Internet—in dorms, classrooms, even under the old oak tree. But now, what once would have been considered abnormal is an active point of discussion: pulling the virtual plug to encourage students to pay more attention in class and become more skilled at real-life social networking. “I have been a bit suspicious about the value of making an entire campus wireless,“ said Lawrence Bacow, former chancellor of MIT, where he was a professor when it began wiring all classrooms in the mid-1990s. “It seems like everyone is always plugged in and always distracted.“ At MIT, where the Internet is accessible even near the banks of the Charles River, students’ eyes obsessively wander, midconversation, down to laptops and cellphones, checking for missed updates from friends. In class, professors complain about students trading stocks online, shopping for Hermes scarves, showing one another video clips on YouTube—leading some faculty to call for the unwiring of all lecture halls. “Students are totally shameless about how they use their computers in class,“ said David Jones, an MIT professor. “I imagine having a Wi-Fi jammer in my lecture halls to block access to distractions.“ While MIT has yet to unwire a single lecture hall, some law schools have in recent years blocked wireless access in classrooms to keep students engaged in Socratic discussions instead of their classmates’ Groupon and eBay activities. Since digital monsters have come, can hunters be far behind?

In the tradition of the company, this dictionary provides especially good coverage and treatment of Americanism—that is, words and idioms that have originated in the United States. In general, the vocabulary treatment is first-rate. The definitions tend to be up-to-date, clearly and precisely written, sufficiently detailed and admirably current. The fullness of the content is without parallel among college dictionaries. Readers will be amazed by the entirely new presentation of the English language as it is written and spoken today. This is a masterpiece of precise defining with the advantage of quotations from well-known writers to demonstrate word usage and to make the book more authoritative.

This team had conducted numerous time-consuming experiments before they verified this hypothesis. advocated denounced simulated confirmed

Those who are addicted to online games can stare at the screen for many hours_______. on the horizon in a row behind the times in the way

The good news was that Mongolia was________enormous reserves of copper and other minerals. blessed with familiarized with charged with involved with

To please shareholders and shoppers, American companies are promising to use more recycled materials in their products. It’s a nice idea, but surprisingly hard to achieve. Most recycled materials should be cheaper than virgin commodities, but America throws too much stuff away. Low landfill fees and a fragmented waste-management system have kept the country’s recycling rate at around 34% for two decades—far lower than most rich countries. Proving the value of recycling is not easy. Industry analysts say $1.25 billion is needed to fully modernize America’s recycling infrastructure. Another challenge is the different incentives of different players. Companies may demand more post-consumer material, but the supply relies on the desire of municipalities and consumers, and there’s no real incentive to maximize recovery or material value. Residents see little benefit from dutiful sorting. Even green-minded folks will throw away a soda can if a recycling bin isn’t readily available. Cities can boost recycling rates with higher landfill taxes or “pay-as-you-throw“ plans, which charge households for the waste they create. But collecting and sorting this material is still a costly, complicated business, and the value of the goods does not always cover the cost of collection. It is also hard to increase the quantity of recycled goods without compromising quality. Many cities now give residents bigger bins and demand less sorting, but the often-contaminated results are a costly headache for recycling companies. One recycling bin ended up holding a six-foot shark. This is a particularly tough time to tell businesses that using more recycled materials makes good economic sense. Falling oil prices have lowered the price of virgin plastic against the recycled stuff, which has upset manufacturers and hurt recycling companies. Without a price on carbon, using recycled commodities does not necessarily help a company’s bottom line. People aren’t going to pay more for recycled plastic just because it’s recycled. In nearly 50 countries, a policy called “extended producer responsibility“ shifts the burden of waste disposal from taxpayers to companies. Such schemes are all over the place when it comes to costs and effectiveness, but they boost recycling rates and save cities money. Thirty-two states already force companies to handle discarded electronics, batteries, mobile phones and other products. Lawmakers in Rhode Island recently introduced a bill that calls on companies to recycle at least 80% of packaging by 2020. If Walmart hopes to prove that voluntary measures will be enough to raise America’s stagnant recycling rates, it will need to work quickly.

For this part, you are to write a composition of no less than 150 words under the title of “Never Too Old to Learn.“ You are advised to avoid using such stereotyped expressions or sentences as “last but not the least.“

It________(2 words) if it was at the theater or just on your own TVGood morning, ladies and gentlemen! Let’s start this introduction to filmmaking with a simple question: How many of you have seen a movie this week? It doesn’t matter if it was at the theater or just on your own TV... Uh-huh, just as I thought; almost all of you have. Of course, most of us love the movies—the magic, the escape that they provide... but most of us rarely stop to think about the process of making a movie. Just what does it take to get that movie from the idea stage to the final product? What are the decisions that must be made? What problems are encountered? Exactly how does a movie studio go about making a movie? These are precisely the topics that we will be exploring today. There are six basic steps that are normally followed in the production of a full-length film. I’ll outline them for you. The first step is rather obvious... to make a film you must have an idea... a story... some topic for the project. The studio must find a property. That’s a key word, folks—property, p-r-o-p-e-r-t-y. You all know the common meaning of this word, of course, but in filmmaking the word “property“ has a very specific meaning. A property is the story on which the movie will be based. OK, it’s the story on which the movie is based. You are probably wondering why we call it a property... Well, it belongs to someone; it is their property and must be acquired by the studio, sometimes for quite a large sum of money. There are basically two kinds of properties. The first is an original story that has never appeared anywhere before—never been in a book, or magazine, or another film. In other words, the story was intended from the very beginning to be made into a movie. Star Wars is one good example of this type of property.