"The world's oceans are slowly getting more acidic,”say scientists. The researchers from California report that the change is taking place in response to higher levels of carbon dioxide in the atmosphere.
The lowering of the waters’pH value is not great at the moment but could cause a serious threat to current ocean life if it continues, they warn. Ken Caldeira and Michael Wickett, from the Lawrence Livermore National Laboratory, report their concerns in the journal Nature.
Increasing use of oil fuels means more carbon dioxide is going into the air, and most of it will eventually be absorbed by seawater. Once in the water, it reacts to form carbonic acid. Scientists believe that the oceans have already become slightly more acidic over the last century.
These researchers have tried to predict what will happen in the future by combining what we know about the history of the oceans with computer models of climate change．"This level of acidity will get much more extreme in the future if we continue releasing CO2 into the atmosphere," said Dr Caldeira. "And we predict the amount of future acidity will exceed（超过）anything we have seen over the last several hundred million years, let alone perhaps after rare disastrous events such as asteroid（小行星) impacts．”
However, it is not absolutely clear what that means for ocean life．Most organisms live near the surface, where the greatest pH change would be expected to occur, but deep-ocean life forms may be more sensitive to pH changes．Coral reefs and other organisms whose shells contain calcium carbonate（小行星) may be particularly affected if the water's acidity levels keep going up, the team predict. They could find it much more difficult to build these structures in water with a lower pH.
In recent years some people have suggested storing carbon dioxide from power stations in the deep ocean as a way of dealing with global warming．But Dr Caldeira said that such a strategy should now be re-considered. "Previously, most experts had looked at ocean absorption of carbon dioxide as a good thing-because in releasing CO2 into the atmosphere we warm the planet, and when CO2, is absorbed by the ocean, it reduces the amount of greenhouse warming.”According to Dr Caldeira,__________ .
| A．ocean absorption of carbon dioxide is a good thing |
| B．more oil fuels will be used in the near future |
| C．scientists may predict climate changes with computer models |
| D．the future situation of the amount of acidity is extremely serious |
f the water's acidity level keeps rising,_________ .
| A．ocean life whose structures contain calcium carbonate may be affected |
| B．the waters’pH value will become higher and higher |
| C．organisms living near the surface are more sensitive to pH changes |
| D．some disastrous events will occur more often than before |
Most experts once believed storing carbon dioxide in the ocean would reduce________ .
| A．the CO2 absorbed by the ocean | B．the amount of greenhouse warming |
| C．the acidity of the ocean | D．the gradual release of CO2 |
The purpose of this passage is to_________ .
| A．show people the findings of a research team | B．inform people of how acid the ocean is now |
| C．introduce Dr Caldeira and his team's research | D．warn people of the higher level of CO2 |
If you want to see climate change, head north and keep going until you run out of globe. That is easier said than done. The Arctic (北极) is home to few people and covered in ice much of the year. But those who make their way to the icy seas of the Arctic Ocean will see a part of the planet that is warming and changing faster than anywhere else.
In September, scientists announced at the National Snow and Ice Data (数据) Center that Arctic summer sea ice had fallen to its second lowest level since 1979, and probably long before that. The Arctic has lost an area of ice greater than the area of all U.S. states east of the Mississippi River. And what ice remains appears to be getting thinner and weaker.
Nick Toberg and Till Wagner are polar ice scientists who are doing sea ice fieldwork. “There is plenty of data to suggest that the ice is becoming thinner as well as smaller in area,” they say.
The changes happening in the Arctic are a warning for the entire world . As polar expert Walt
Meier puts it, “What happens in the Arctic doesn’t stay in the Arctic.”
Some scientists worry that Arctic sea ice may be going from a downward spiral (螺旋线) to a “death spiral”, one from which there is no escape. As more ice melts (融化), more dark open water appears. The darkness absorbs (吸收) more heat, which speeds up the pace of melting.
Until recently, many scientists thought it might take until the end of the century for the North Pole to become completely ice free during the summer. Now some believe it could happen by 2030 or even earlier. “The melting is happening faster in the real world than it has in the models,” says Nick Toberg. The purpose of the first paragraph is to tell readers __________.
| A．it’s difficult to arrive at the Arctic |
| B．it is too cold for people to live in the Arctic |
| C．what caused the climate change in the Arctic |
| D．we can see the most obvious climate change in the Arctic |
From the second paragraph we can learn Arctic summer sea ice __________.
| A．is still decreasing |
| B．began reducing in 1979 |
| C．fell to its lowest level in September |
| D．is equal to the Mississippi River |
What does the underlined sentence in Paragraph 3 mean?
| A．The changes don’t affect the Arctic at all. |
| B．The changes will only happen in the Arctic. |
| C．The changes happening in the Arctic will stop. |
| D．The changes will also affect other parts of the world. |
Nick Toberg may agree that __________.
| A．the ice in the North Pole will stop melting |
| B．the ice in the North Pole is melting faster than expected |
| C．the ice in the North Pole will melt before 2030 or even earlier |
| D．the ice in the North Pole will not disappear until the end of the century |
Nelson Mandela was a figure of international fame, and many details of his life and career were public knowledge. But here are four things you may not have known about the late South African leader.
1. He was a boxing fan.
In his youth, Nelson Mandela enjoyed boxing and long-distance running. Even during the 27 years he spent in prison, he would exercise every morning. "I did not enjoy the violence of boxing so much as the science of it. I was curious by how one moved one's body to protect oneself, how one used a strategy both to attack and retreat, how one paced oneself over a match," he wrote in his autobiography Long Walk to Freedom.
2. His original name was not Nelson.
Rolihlahla Mandela was nine years old when a teacher at the primary Methodist school where he was studying in Qunu, South Africa, gave him an English name “Nelson” in accordance with the custom to give all school children Christian names.
3. He forgot his glasses when he was released from prison.
Mr. Mandela's release on 11 February 1990 followed years of political pressure against apartheid(种族隔离). Mr. Mandela's reading glasses stayed behind in prison. Mr. Mandela and his then-wife Winnie were taken to the centre of Cape Town to address a huge and exciting crowd. But when he pulled out the text of his speech, he realized he had forgotten his glasses and had to borrow Winnie's.
4. He had his own law firm, but it took him years to get a law degree.
Mr. Mandela studied law on and off for 50 years from 1939, failing about half the courses he took. A two-year diploma(学位证书) in law on top of his university degree allowed him to practice, and in August 1952, he and Oliver Tambo set up South Africa's first black law firm, Mandela and Tambo, in Johannesburg. He kept on studying hard to finally secure a law degree while in prison in 1989.What is the main idea of the passage?
| A．Nelson Mandela’s life in the prison. |
| B．Unknown things about Nelson Mandela. |
| C．Nelson Mandela’s hobbies and career. |
| D．The achievements of Nelson Mandela. |
Why did Nelson Mandela love boxing?
| A．Because he wanted to be a boxer. |
| B．Because he loved the science in boxing. |
| C．Because he enjoyed the violence of boxing. |
| D．Because he had nothing else to do in the prison. |
What happened to Mandela when he was about to give the speech?
| A．He broke his glasses into pieces. |
| B．He left his own glasses at home. |
| C．He had to use his wife’s glasses. |
| D．His wife wanted to borrow his glasses. |
Which of the following is NOT true according to the passage?
| A．Nelson Mandela was not his original name. |
| B．Nelson Mandela was the name given by his teacher. |
| C．Nelson Mandela had started his own law firm before he got a law degree. |
| D．Nelson Mandela had been studying the law nonstop for 50 years. |
In 1978, I was 18 and was working as a nurse in a small town about 270 km away from Sydney, Australia. I was looking forward to having five days off from duty. Unfortunately, the only one train a day back to my home in Sydney had already left. So I thought I’d hitch a ride (搭便车).
I waited by the side of the highway for three hours but no one stopped for me. Finally, a man walked over and introduced himself as Gordon. He said that although he couldn’t give me a lift, I should come back to his house for lunch. He noticed me standing for hours in the November heat and thought I must be hungry. I was doubtful as a young girl but he assured (使……放心)me I was safe, and he also offered to help me find a lift home afterwards. When we arrived at his house, he made us sandwiches. After lunch, he helped me find a lift home.
Twenty-five years later, in 2003, while I was driving to a nearby town one day, I saw an elderly man standing in the glaring heat, trying to hitch a ride. I thought it was another chance to repay someone for the favor I’d been given decades earlier. I pulled over and picked him up. I made him comfortable on the back seat and offered him some water.
After a few moments of small talk, the man said to me, “You haven’t changed a bit, even your red hair is still the same.”
I couldn’t remember where I’d met him. He then told me he was the man who had given me lunch and helped me find a lift all those years ago. It was Gordon.The author(作者) had to hitch a ride one day in 1978 because __________ .
| A．the town was far away from Sydney |
| B．she missed the only train back home |
| C．she was going home for her holidays |
| D．her work delayed her trip to Sydney |
Which of the following did Gordon do according to Paragraph 2?
| A．He bought sandwiches for the girl . |
| B．He gave the girl a ride back home. |
| C．He helped the girl find a ride. |
| D．He watched the girl for three hours. |
The reason why the author offered a lift to the elderly man was that __________.
| A．she realized he was Gordon |
| B．she had known him for decades |
| C．she was going to the nearby town |
| D．she wanted to pay back the help she once got |
What does the author want to tell the readers through the story?
| A．Sometimes giving produces nice results. |
| B．Those who give rides will be repaid. |
| C．Good manners bring about happiness. |
| D．People should offer free rides to others. |
Most people are aware of what the adoption process is because it has become rather common in our society. Adoption is where a child is legally placed with guardians (监护人) or parents (or perhaps a single parent) other than the birth mother or father. Once an adoption is finalized, all parental rights are turned over to the adoptive parents and there is no legal difference between adoptive parents and natural birth parents. There are generally two types of adoption, which are closed adoption and open adoption.
When an adopted person has access to his or her adoption file and original records, it is referred to as an open adoption. The term is also used to describe any contact that may be between the adoptive family, the birth parents, and the adopted child. The level of openness can change greatly in such contact depending on each individual relationship. There can be indirect contact between the natural birth parents and the child through the form of letters and photographs, or there can be actual physical contact.
A semi-open adoption is where the birth parents may have contact with the adoptive parents before the birth of the child, either once or several times. After the birth there is no more contact. A semi-open adoption may remain as it is or it can become either open or closed.
A closed adoption is where only the medical and historical information about the biological parents is given to the adoptive family. Typically, the birth and adoptive parents do not know each other’s identities. The record of the birth parents is kept sealed (密封). A closed adoption is usually only effective in the adoption of babies. The adoption of an older child who already knows his or her birth parents cannot be kept closed.How many adoption types are mentioned in the passage?
| A．2. | B．3. | C．4. | D．5. |
Which of the following statements is TRUE about the closed adoption?
| A．The birth parents may have indirect contact with the adoptive parents. |
| B．The biological parents may often go to see their birth child. |
| C．No information about the biological parents is given to the adoptive parents. |
| D．Generally speaking, the adoptive parents do not know the birth parents’ identities. |
Suppose someone adopts a child and his biological parents often get contact with the child by telephone. We can call this adoption _____.
| A．a closed adoption | B．an open adoption |
| C．a semi-open adoption | D．a semi-closed adoption |
From the passage, we know adoption is _____.
| A．where a child is brought up by the government |
| B．where a child is legally sent abroad by the birth parents |
| C．where a child is legally placed with adoptive parents |
| D．where a child is sent to live with the children whose parents have died |
You might not know it, but there is something wonderful at your fingertips. You can make people happier, healthier and more hard-working just by touching their arms or holding their hands.
Doctors say that body contact is a kind of medicine that can work wonders. When people are touched, the quantity of hemoglobin (血红蛋白)－a type of matter that produces the red color in blood increases greatly. This results in more oxygen reaching every part of the body and the whole body benefits. In experiments, bottle-fed baby monkeys were separated from their mothers for the first ten days of life. They became sad and negative. Studies showed the monkeys were more probable to become ill than other babies that were allowed to stay with their mothers.
Human babies react in much the same way. Some years ago, a scientist noticed that some well-fed babies in a clean nursery became weak. Yet babies in another nursery were growing healthily, even though they ate less well and were not kept as clean. The reason, he concluded, was that they often had touches from nurses.
Experiments show that most people like being touched. And nearly all doctors believe touch helps to reduce patients' fear of treatment. Of course there is time when a touch is not welcome. But even if we don't like being touched, a smile can make us feel better. Smiling increases blood flow and starts the production of "happy brain" chemicals. So let's have a big smile and don't forget to keep in touch.Which of the following is NOT true?
| A．Everyone knows that body contact can make people happier. |
| B．People may work harder because of body contact. |
| C．Your fingertips can do something. |
| D．People may not understand the importance of touching. |
According to the passage _____.
| A．human brains need oxygen and blood supply now and then |
| B．touches from doctors and nurses have nothing to do with treatment |
| C．new-born baby monkeys should stay away from their mothers |
| D．not all the people like being touched |
The word "benefits" in the second paragraph probably means _____.
| A．to be useful or helpful |
| B．to get something useful or helpful |
| C．to be ill |
| D．to be hurt |
The best title for the passage might be _____.
| A．Why People Touch | B．Smile and Touch |
| C．Wonders of Touch | D．Touch or Not |
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