When prehistoric man arrived in new parts of the world, something strong happened to the large animals; they suddenly became extinct. Smaller species survived; the large, slow-growing animals were easy game, and were quickly hunted to extinction. Now something similar could be happening in the oceans. That the seas are being over-fished has been known for years and researchers such as Ransom Myers and Boris Worm have shown how fast things are changing. They have looked at half a century of data from fisheries around the world. Their methods do not attempt to estimate the actual biomass (the amount of living biological matter) of fish species in particular parts of the ocean, but rather changes in that biomass over time. According to their latest paper published in Nature, the biomass of large predators (animals that kill and eat other animals) inanes fishery is reduced on average by 80% within 15 years of the start of exploitation. In some long-fished areas, it has halved again since then. Dr. Worm acknowledges that these figures are conservative . One reason for this is that fishing technology has improved. Today's vessels can find their prey using satellites and sonar, which were not available 50 years ago. That means a higher proportion of what is in the sea is being caught, so the real difference between present and past is likely to be worse than the one recorded by changes in catch sizes. In the early days, too, longlines would have been more saturated with fish. Some individuals would therefore not have been caught, since baited hooks would have been available to trap them, leading to an underestimate of fish stocks in the past. Furthermore, in the early days of longline fishing, a lot of fish were lost to sharks after they had been hooked. That is no longer a problem, because there are fewer sharks around noise. Dr. Myers and Dr. Worm argue that their work gives a correct baseline, which future management efforts must take into account. They believe the date support an idea current among marine... We can infer from Dr Myers and Dr. Worm's paper that _ . A) the stock of large predators in some old fisheries has reduced by 90% B) there are only half as many fisheries are there were 15 years ago C) the catch sizes in new fisheries are only 20% of the original amount D) the number of larger predators dropped faster in new fisheries than in the old
A
WASHINGTON----Chinese Vice-President Xi Jinping arrived at Andrews Air Force Base in Washington,February 13,2012.Vice-President Xi Jinping said he would explore important problems in an active and practical manner with his America hosts on Monday during his five-day official trip here after arriving at Andrews Air Force Base in the afternoon. In a written statement given upon his arrival,Xi said as the international situation experiences complex and complete changes,China and the United States have more extensive common interests and shoulder more important common responsibilities on the present world stage. The purpose of the current visit is to "carry out the important _ reached by President Hu with President Obama during his visit to the United States in January last year and to advance the building of the China--US cooperative partnership based on mutual respect and mutual benefit",said Xi. According to Xi,bilateral relations have moved forward in spite of some twists and turns during the past several decades. "This has brought enormous benefits to our two countries and two peoples,and has had a positive, far-reaching impact on peace,stability and the prosperity of the Asia-Pacific region and the world at large". Xi said that"whether we can seize opportunities,tackle challenges and build a cooperative partnership at the new historical starting point matters to the future of our two countries and the world as a whole." Xi said he looks forward to engaging in extensive dialogue and exchanges with Americans from various sectors to enhance cooperation and strengthen friendship. Xi is scheduled to meet US senior government officials,including Henry Kissinger,Brent Scowcroft,Zbigniew Brzezinski,Madeleine Albright and Henry Paulson this evening to listen to their advice on China-US ties. Meetings between Xi and US Vice-President Biden and President Obama are scheduled on Tuesday. According to tile passage,bilateral relations between China and US have experienced _ . A) enormous dialogues B) extensive exchanges C) rnany challenges D) various hardships
D
Q: David is an excellent student and he comes from New York. His family was there until he finished eighth grade. David had no choice but to sleep on park benches. Being alone on the streets was scary. One thing kept David going: his determination to do well in school. Even though many things were difficult in David's life, one thing was going very well. David was accepted to a special high school called MC2STEM.It is a public school in Cleveland for kids who are extremely good at science. The school turned out a peaceful place for David. He especially enjoyed having the chance to learn by doing lots of projects. High school wasn't easy. But David says that the school helped him set high standards for himself. Even when he didn't have a place to stay at night, David kept his focus on his schoolwork. While he was homeless, David would sometimes sleep in the park during the day because it was safer. " If you sleep in the daytime in the park, people won't bother you," he says. "you're just taking a nap. It's acceptable." Then David would study through the night. He showered at a friend's house when his friend's parents were at work. All his hard work paid off. In May 2011, David graduated second in his high school class. He was accepted to 22 colleges. He also won a scholarship form the Bill and Melinda Gates Foundation. It will pay for all his college expenses. Last fall, David began attending Harvard University, one of the top colleges in the US."I found the perfect school for me." He wrote in his blog. In the future, David might look for a job at a company like Google. Even better, he would like to start his own company. David says, " I want to work for myself." What's the best title for the passage? A) A top University B) A Poor Student C) Homeless to Harvard D) Winning a Scholarship
A: C
(Question)
At least 3 people are dead in the Philippines now that Typhoon Hagupit has landed. The typhoon, which hit the eastern Philippines over the weekend, has blown down trees and sent more than 650thousand people into shelters before weakening. "There were very strong winds last night. The roof was beginning to move, and rain was getting inside the rooms," said a villager. The storm hit with gusts of over 100 miles per hour. And while the storm has slowed considerably from the super typhoon level it had last week, Hagupit still remains strong enough to create more damage. Christopher Perez is a local weather forecaster. He says, "We are continuing to expect bad weather and rough ocean waves. Threats of possible flash floods and landslides as well as possible storm waves are occurring in coastal areas." Hagupit is expected to roll into the South China Sea tomorrow. It's currently going westward toward the southern tip of Vietnam, meaning it's unlikely to affect China. Hagupit's strength in the Philippines is much less severe than Typhoon Haiyan, which rolled through the country in 2013. Haiyan's tsunamilike storm waves and killer winds left thousands of people dead and _ . The central Philippines is still trying to recover from last year's massive storm waves. Which of the following places suffered most when Typhoon Haiyan rolled in? A) The eastern Philippines. B) The southern tip of Vietnam. C) The South China Sea. D) The central Philippines.
(Answer)
D