2014年英语四级听力的练习：VOA慢速4.19

　　下面是4月19日VOA慢速听力的英文原文，供考生参考。

　　Hello again, and welcome to As It Is! Im Jonathan Evans in Washington.

　　Today on the program, we have great news for all of our listeners. By learning English in addition to your own language, you could delay or prevent many forms of mental decline! Milagros Ardin has the story.

　　Speaking More than One Language Could Delay Dementia

　　New research suggests that speaking more than one language may delay different kinds of dementia. That is, the loss of mental ability. In fact, researchers say speaking two languages appears to be more important than the level of education in defending against dementias.

　　A study in India examined the effect of knowing more than one language in delaying the first signs of several disorders. These included Alzheimers disease, frontotemporal dementia, vascular dementia, Lewy bodies dementia and mixed dementias.

　　Researchers studied nearly 650 people whose average age was 66. Two hundred forty of those studied suffered from Alzheimers -- the most common form of mental decline.

　　Three-hundred-ninety-one of the subjects spoke two or more languages. Investigators found the dementias began about four-and-a-half years later in those who were bilingual compared to those who spoke only one language. The level of education had no effect on the age at the first sign of dementia.

　　Thomas Bak helped to organize the study. He is with the Center of Cognitive Aging at the University of Edinburgh in Scotland. He suggests that individuals who speak more than one language train their brains by moving back and forth between different words and expressions.

　　Mr. Bok believes this effort improves what scientists call executive functioning or attention to tasks. This mental ability often weakens in people with dementias.

　　Researchers found there was no extra gain in speaking more than two languages. They also did not see a delay in the first signs of Lewy bodies dementia. The disorder causes patients to see or experience things that do not really exist. It can also cause sufferers to move back and forth between being wide awake and really sleepy.

　　Mr. Bak says it does not appear important whether you learn a language at a young age or later in life.

　　So its not something you sort of say that ) you missed the boat when you do not do it as a baby. It is something that is still quite useful and powerful when you do it as an adult.

　　Scientists found that speaking more than one language helped delay the first signs of dementias even in those who could not read. An article on the benefits of bilingualism on dementias is published in the journal Neurology.

　　Im Milagros Ardin.

　　And Im Jonathan Evans. You are listening to As It Is from VOA Learning English.

　　Many people around the world die from smoking-related diseases such as lung cancer. But millions of lives could be saved in China if the country had tougher anti-smoking rules. Here again is Milagros Ardin.

　　Anti-Smoking Rules Could Prevent Millions of Deaths in China

　　Local men smoke cigarettes in Shanghai, China.

　　?A new study finds that more than 13 million deaths could be prevented in China over the next 40 years if the country had stronger anti-smoking measures. But the studys authors say China has not taken many steps to control the use of tobacco. The study was published in the British Medical Journal.

　　China signed the World Health Organizations international treaty on tobacco control in 2003. But it has not put in place many of the WHO ideas to help people stop smoking. Experts say following these ideas could cut smoking by 40 percent before the year 2050. Without stronger anti-smoking measures, there could be 50 million tobacco-related deaths in the country over that time.The authors of the study used a computer program called SimSmoke to make their predictions.

　　David Levy works at Georgetown Universitys Lombardi Cancer Center in Washington, DC. He says China has one third of the worlds cigarette smokers. More than half of the men in China smoke. Mr. Levy says people often begin smoking without knowing it will harm their health. He says people in some countries smoke because it makes them feel important.

　　Smoking, you know, once it gets established and in many of the low- and middle income countries, you know theres a kind of a prestige initially to smoking.

　　The WHO plan calls for a ban on smoking in all public places. It also calls for countries to place health warnings on cigarette containers and offer programs to help people stop smoking. And, it says, there should be high taxes on tobacco.

　　Experts say a 75 percent increase in cigarette taxes could save about 3.5 million lives. They say an end to cigarette advertising could save two million lives. After signing the WHO agreement, China placed a 12 percent tax on cigarettes. But the government did not force Chinese smokers to pay the tax.

　　One of the authors of the new study is Teh-we Hu. He is a professor of public policy economics at the University of California Berkeley. Professor Hu says Chinas culture and society are changing. He says President Hu Jintao supports a ban on smoking in public. The president also wants people to stop giving cigarettes as gifts to officials and employers. Mr. Hu says the most effective anti-smoking measure in China would be a large increase in the cigarette tax. But he does not expect that to happen soon.

　　Im Milagros Ardin.

　　And thats our program for today. Join us again tomorrow for another edition of As It Is. Im Jonathan Evans. Thanks for listening!