There is extraordinary exposure in the United States to the risks of injury and death from motor vehicle accidents.More than 80 percent of all households own passenger cars or light trucks and each of these is driven an average of more than 11，000 miles each year.Almost one-half of fatally injured drivers have a blood alcohol concentration (BAC) of 0.1 percent or higher.For the average adult，over five ounces of 80 proof spirits would have to be consumed over a short period of time to attain these levels.One third of drivers who have been drinking，but fewer than 4 percent of all drivers，demonstrate these levels.1)Although less than 1 percent of drivers with BACs of 0.1 percent or more are involved in fatal crashes，the probability of their involvements is 27 times higher than for those without alcohol in their blood.There are a number of different approaches to reducing injuries in which drinking plays a role.Based on the observation that excessive consumption correlates with the total alcohol consumption of a country‘s population，it has been suggested that higher taxes on alcohol would reduce both.While the heaviest drinkers would be taxed the most，anyone who drinks at all would be punished by this approach.
To make drinking and driving a criminal offense is an approach directed only at drinking drivers.In some states，the law empowers police to request breath tests of drivers committing any traffic offense and higher BAC can be the basis for arrest.The National Highway Traffic Safety Administration estimates，however，that even with increased arrests，there are about 700 violations for every arrest.At this level there is little evidence that laws are effective ways to reduce drunk driving.In Britain，motor vehicle accidents fell 25 percent immediately following implementation of the Road Safety Act in 1967. 2) As Britishers increasingly recognized that they could drink and not be stopped，the effectiveness declined，although in the following three years the death-rate seldom reached that observed in the seven years prior to the Act.
Whether penalties for driving with a high BAC or excessive taxation on consumption of alcoholic drinks will deter the excessive drinker responsible for most accidents is unclear.One thing is clear，however：unless we deal with automobile and highway safety and reduce accidents in which alcoholic drinking plays a role，many will continue to die.
1.The author is primarily concerned with____.
[A] interpreting the results of surveys on traffic accidents
[B] reviewing the effectiveness of attempts to reduce drunk driving
[C] analyzing the causes of the large number of annual traffic deaths
[D] making an international comparison of experience with drunk driving
2.It can be inferred that the 1967 Road Safety Act in Britain____.
[A] changed an existing law to lower the BAC level which defined drunk driving
[B] made it illegal for the drunk driver to drive
[C] increased the number of drunk driving arrests
[D] placed a tax on the sale of alcoholic drinks
3.The author implies that a BAC of 0.1 percent ____. the sale of alcoholic drinks
[A] is unreasonably high as a definition of drunk driving
[B] penalizes the moderate drinker while allowing the heavy drinker to consume without limit
[C] is well below the BAC of most drivers who are involved in fatal crashes
[D] proves that a driver has consumed five ounces of 80 proof spirits over a short time
4.The author cites the British example in order to____.
[A] show that the problem of drunk driving is worse in Britain than in the U.S.
[B] prove that stricter laws against drinking drivers would reduce traffic deaths
[C] prove that a slight increase in the number of arrests of drunk drivers will not deter drunk driving
[D] suggest that taxation of alcohol consumption may be more effective than criminal laws
5.The word“deter”in the last paragraph probably means____.
3.[A] 根据第一段第五、六句，1/3的酒后驾车者能达到这个含量(BAC of 0.1 %)，但是这还不到所有驾驶员人数的4 %.虽然在达到或超过0.1 %的人中不到l %卷人致命的事故中，但是，他们出事的可能性是不喝酒的人的28倍。由此可见，在作者看来，还有很多没有达到这个含量的人也同样危险，因此，0.1 %的含量标准太高了。