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【单选题】
The world’s rainforests cover less than ten percent of the earth’s suce, but contain over forty percent of all plant and animal species. The biggest rainforest is in South America, it’s called the Amazon.
Amazon is by far the largest remaining rainforest area left on our planet. It’s about 6 to 7 million square kilometers. It’s about two-thirds the size of the United States including Alaska. It’s enormous. Sixty percent of it is in Brazil, but the rainforest also extends into Bolivia, Peru, Ecuador, Colombia, Venezuela, French Guiana and Surinam. And amazingly each year the Amazon provides twenty percent of the world’s fresh water. Here you can find at least 60-70 thousand plant species and at least 3 thousand species of fresh water fish. And more monkeys than you find anywhere else on earth. In Brazil alone nine new species of monkeys have been identified over the last year.
But many of those species, known and unknown, are destroyed every day. Moreover, constant logging, mining and raising domestic animals cause a gradual disappearance of the Amazon jungles.
Over forty percent of all plant and animal species on the earth live in ______.
A.
the sea
B.
the rainforests
C.
the grassland
D.
E.
D. the desert
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【单选题】Insurance Whole life is permanent insurance protection that protects you for your whole life, from the day you purchase the policy until you die, as long as you pay the premiums (保险费). Whole life can...
A.
It’s permanent insurance protection from the day you were born until you die.
B.
It’s permanent insurance protection that protects you for your whole life, from the day you buy it until you die.
C.
It’s insurance protection for your whole family members.
D.
It’s income protection insurance.
【单选题】Calling for Safe Celebrations Last Fourth of July, Pete, a 14-year-old boy, was enjoying the lit-up skies and loud booms from the fireworks(烟花) being set off in his neighborhood. Suddenly, the evening...
A.
About 9,000.
B.
About 4,500.
C.
About 1,350.
D.
About 30.
【单选题】Sleeping People who sleep for more than eight hours a night do not live as long as those who sleep for six hours, according to the biggest study yet into sleep patterns and mortality(死亡率). Scientists...
A.
Although it is a common belief that sleeping for at least eight hours a night is vital for health and well—being. the six. year study involving more than 1. 1 million Americans older than 30 found that those who slept for less than eight hours were far from doing themselves any long—term harm。
B.
"Individuals who now average 6. 5 hours of sleep a night Can be reassured that this is a safe amount of sleep. From a health standpoint。there is no reason to sleep longer," said Daniel Kripke , a professor of psychiatry(精神病学)at the University of California, San Diego.
C.
Dr. Kripke said. "We don’t know if long sleep periods lead to death. Additional studies are needed to determine if setting your alarm clock earlier will actually improve your health. "
D.
The scientists. who were funded by the American Cancer Society, found at the best survival rates were among the men and women who slept for seven hours a night. Those who
E.
slept for eight hours were 12 per cent more likely to die during the six—year period of the study,
F.
when other factors such as diet and smoking were taken into account.
G.
Even those who spent a mere five hours a night in bed lived longer than those who slept eight or more hours. However, an increasing death rate was found among those who slept for less than five hours.
H.
Dr. Kripke said. "Previous sleep studies have indicated that both short-and long-duration(持续时间)sleep had higher mortality rates. However, none of those studies were large enough to distinguish the difference between seven and eight hours a night, until flow. \
【单选题】Sleeping People who sleep for more than eight hours a night do not live as long as those who sleep for six hours, according to the biggest study yet into sleep patterns and mortality(死亡率). Scientists...
A.
Although it is a common belief that sleeping for at least eight hours a night is vital for health and well—being. the six. year study involving more than 1. 1 million Americans older than 30 found that those who slept for less than eight hours were far from doing themselves any long—term harm。
B.
"Individuals who now average 6. 5 hours of sleep a night Can be reassured that this is a safe amount of sleep. From a health standpoint。there is no reason to sleep longer," said Daniel Kripke , a professor of psychiatry(精神病学)at the University of California, San Diego.
C.
Dr. Kripke said. "We don’t know if long sleep periods lead to death. Additional studies are needed to determine if setting your alarm clock earlier will actually improve your health. "
D.
The scientists. who were funded by the American Cancer Society, found at the best survival rates were among the men and women who slept for seven hours a night. Those who
E.
slept for eight hours were 12 per cent more likely to die during the six—year period of the study,
F.
when other factors such as diet and smoking were taken into account.
G.
Even those who spent a mere five hours a night in bed lived longer than those who slept eight or more hours. However, an increasing death rate was found among those who slept for less than five hours.
H.
Dr. Kripke said. "Previous sleep studies have indicated that both short-and long-duration(持续时间)sleep had higher mortality rates. However, none of those studies were large enough to distinguish the difference between seven and eight hours a night, until flow. \
【单选题】The importance and focus of the interview in the work of the print and broadcast journalist is reflected in several books that have been written on the topic. Most of these books, as well as several c...
A.
a news article
B.
a journalistic interview
C.
a research report
D.
a preface
【单选题】Cell Phone Lets Your Secret Out Cell Phone Lets Your Secret Out52（） A.appeals B.appoint C.appears D.applies
A.
Your cell phone holds secrets about you. Besides the names and (51) that you’ve programmed into it, traces of your DNA linger (逗留) on the device, according to a new study.
B.
DNA is genetic material that (52) in every cell. Like your fingerprint, your DNA is unique to you (53) you have an identical twin. Scientists today routinely analyze DNA in blood, saliva (唾液), or hair left (54) at the scene of a crime. The results often help detectives identify (55) and their victims. Your cell phone can reveal more about you (56) you might think.
C.
Meghan J. McFadden, a scientist at McMaster University in Hamilton, Ontario, heard about a crime in which the suspect bled onto a cell phone and later dropped the (57) . This made her wonder whether traces of DNA lingered on cell phones even when no blood was involved. (58) , she and colleague Margaret Wallace of the City University of New York analyzed the flip-open phones of 10 volunteers. They used swabs (药签) to collect (59) traces of the users from two parts of the phone: the outside, where the user holds it, and the (60) , which is placed at the user’s ear.
D.
The scientists scrubbed the phones using a solution made mostly (61) alcohol. The aim of washing was to remove all detectable traces of DNA. The owners got their phones (62) for another week. Then the researchers collected the phones and repeated the swabbing of each phone once more.
E.
The scientists discovered DNA that (63) to the phone’s speaker on each of the phones. Better samples were collected from the outside of each phone, but those swabs also picked up DNA that belonged to other people who had apparently also handled the phone. (64) , DNA showed up even in swabs that were taken immediately after the phones were scrubbed (擦洗). That suggests that washing won’t remove all traces of evidence from a criminal’s device. So cell phones can now be added to the (65) of clues that can decide a crime-scene investigation.