第四部分：阅读理解

短文后有5道题，每题后面有4个选项。请仔细阅读短文并根据短文回答其后面的问题，从4个选项中选择1个最佳答案涂在答题卡相应的位置上。

第一篇 A New Strategy to Overcome Breast Cancer

Post-menopausal（绝经后）women who walk for an hour a day can cut their chance of breast cancer significantly ， a study has suggested. The report ，which followed 73，000 women for 17 years ， found walking for at least seven hours a week lowered the risk of the disease . The American Cancer Society team said this was the first time reduced risk was specifically linked to walking. UK experts said it was more evidence that lifestyle influenced cancer risk.

A recent poll for the charity Ramblers a quarter of adults walk for no more than an hour a week ， but being active is known to reduce the risk of a number of cancers . This study， published in Cancer Epidemiology ， Biomarkers & Prevention ， followed 73.615 women out of 97，785 aged 50-74 who had been recruited by the American Cancer Society between 1992 and 1993，so it could monitor the incidence of cancer in the group.

They were asked to complete questionnaires on their health and on how much time they were active and participating in activities such as walking ， swimming and aerobics（有氧运动）and how much time they spent sitting watching television or reading . They completed the same questionnaires at two-year intervals between 1997 and 2009.Of the women，47% said walking was their only recreational activity . Those who walked for at least seven hours per week had a 14% lower risk of breast cancer compared to those who walked three or fewer hours per week.

Dr. Alpa Patel ， a senior epidemiologist at the American Cancer Society in Atlanta ， Georgia ， who led the study ， said：“Given that more than 60% of women report some daily walking ， promoting walking as a healthy leisure-time activity could be an effective strategy for increasing physical activity amongst post-menopausal women . We were pleased to find that without any other recreational activity， just walking one hour a day was associated with a lower risk of breast cancer in these women.”“More strenuous（紧张的）and longer activities lowered the risk even more.”

Baroness Delyth Morgan， chief executive of Breast Cancer Campaign ， said：“This study adds further evidence that our lifestyle choices can play a part in influencing the risk of breast cancer and even small changes incorporate into our normal day-to-day activity can make a difference.”

She added：“We know that the best weapon to overcoming breast cancer is the ability to stop it occurring in the first place. The challenge now is how we turn these

findings into action and identify other sustainable lifestyle changes that will help us prevent breast cancer.“

第二篇

Around 45% of the UK‘s carbon dioxide emissions come from the energy people use every——at home and when they travel . In order to generate that energy， fossil fuels （coal oil， and gas） are burnt， and these produce greenhouse gases—— in particular carbon dioxide （CO2） a year， and it is the same CO2 that is changing the climate and damaging the environment.

CO2 and various other gases wrap the earth in an invisible blanket helping to prevent heat from escaping. Without this greenhouse effect， the average temperature on Earth would be around -18℃， compared with the current average of around +15℃。 The composition of this blanket of gases has remained relatively constant for many thousands of years. However， since the industrial revolution began around 200 years ago， people have been burning increasing amounts of fossil fuels， thus releasing more CO2 and other greenhouse gases in the process. This has increased the heating effect of the blanket， trapping more of the sun‘s energy inside the Earth’s atmosphere in turn the Earth‘s temperature has increased more rapidly in a shorter pennd of there that it has for thousands of years.

In 2008， the total UK CO2 emissions were 533 million tones 27% （144 million tonnes ） of those emissions came from the energy used to heat， light， and power homes. Transport emissions caused by passenger cars， buses and motorcycles accounted for a further 16% （87 million tonnes ） of the UK‘s CO2 emissions. These figures show that a significant amount of CO2 results from ordinary citizens’ carbon footprint in their daily activities and lifestyle.

The effects of climate change can be seen all around us. Weather patterns are cecoming more and more fractured and uncertain， and over the last century trends in warm weather have become increasingly common. In the UK in the last 40 years， winters have grown warmer with much heavier rainfall. One of the clearest shifts over the last 200 years is towards summers that are hotter and drier， causing pervasive water shortages. Recent years have been the hottest since records began and during August 2003 the hottest outdoor temperature in the UK was recorded ——38.5.

第三篇：First Sell-contained Heart Implanted

A patient on the brink of death has received the world‘s first self-contained artificial heart—a battery-powered device about the size of a softball that runs without the need for wires， tubes or hoses sticking out of the chest.

Two surgeons from the University of Louisville implanted the titanium and plastic pump during a sever-hour operation at Jewish Hospital Monday. The hospital said the patient was “awake and responsive” Tuesday and resting comfortably. It refused to release personal details.

The patient had been expected to die within a month without the operation， and doctors said they expected the artificial heart to extend the person‘s life by only a month. But the device is considered a major step toward improving the patient’s quality of life.

The new pump， called AbioCor， is also a technological leap from the mechanical hearts used in the 1980s， which were attached by wires and tubes to bulky machinery outside the body. The most famous of those， the Jarvic-7， used air as a pumping device and was attached to an apparatus about the size of a washing machine.

“I think it‘s potentially a major step forward in the artificial heart development，” said Dr. David Faxon， president of the American heart Association. However， he said the dream of an implantable， permanent artificial heart is not yet a reality： “This is obviously an experimental device whose long-term success has to be demonstrated.”

Only about half of the 4，200 Americans on a waiting list for donor hearts received them last year， and most of the rest died. Some doctors， including Robert Higgins， chairman of cardiology at the Medical College of Virginia in Richmond， said artificial hearts are unlikely to replace donor hears.

“A donor heart in a good transplant can last 15 to 30 years，” he said. “It‘s going to be hard to replace that with a machine.”