An alcohol breath test(ABT)is often used by the police to find out whether a person is drunk while driving.In the United States，the legal blood alcohol limit is 0.08%for people aged 21 years or older，while people under 21 are not allowed to drive a car with any level of alcohol in their body.A“positive”test result，a result over the legal limit，allows the police to arrest the driver.However，many people who tested positive on the test have claimed that they only drank a“non­alcoholic”energy drink.Can one of these energy drinks really cause someone to test positive on an ABT?Researchers in Missouri set up an experiment to find out.
　　First，the amount of alcohol in 27 different popular energy drinks was measured.All but one had an alcohol level greater than 0.005%.In nine of the 27 drinks，the alcohol level was at least 0.096%.The scientists then investigated the possibility that these small levels of alcohol could be discovered by an ABT.They asked test subjects to drink a full can or bottle of an energy drink and then gave each subject an ABT one minute and 15 minutes after the drink was finished.
　　For 11 of the 27 energy drinks，the ABT did find the presence of alcohol if the test was given within one minute after the drink was taken.However，alcohol could not be discovered for any of the drinks if the test was given 15 minutes after the drink was consumed.This shows that when the test is taken plays an important role in the test result.The sooner the test is conducted after the consumption of these drinks，the more likely a positive alcohol reading will be obtained.
　　1、Which of the following is true according to the passage?
　　A.A driver whose blood alcohol level is found to be 0.1%will be arrested.
　　B.No energy drinks really cause anyone to test positive on an ABT.
　　C.Few popular energy drinks contain alcohol in them.
　　D.Those taking an ABT 15 minutes after drinking alcohol cannot be found out.
　　参考答案：A
　　参考解析：推理判断题。根据文章第一段可知，合法的血液酒精浓度最高值应该是0.08%，如果超过这个浓度，司机就会被警察逮捕。由此可推知，答案A符合文意。
　　2、What is the legal alcohol level for a 20­year­old driver in the US?
　　A.0.000%.
　　B.0.005%.
　　C.0.080%.
　　D.0.096%.
　　参考答案：A
　　参考解析：细节理解题。根据文章第一段第二句“In the United States，the legal blood alcohol limit is 0.08%for people aged 21 years or older，while people under 21 are not allowed to drive a car with any level of alcohol in their body.”可知，答案A符合文意。
　　3、The underlined word“subjects”in Paragraph 2 refers to________.
　　A.the things that are being discussed
　　B.areas of knowledge studied in school
　　C.the participants in an experiment
　　D.the people who belong to a country
　　参考答案：C
　　参考解析：词义猜测题。根据语境可知，文章中画线句子的意思是：他们要求参加测试的实验者喝下一满听或一瓶能量饮料，然后在一分钟和十五分钟后对其ABT进行测试。由此可推知，此处的subject是指参与实验的人。
　　4、What is the purpose of the Missouri experiment?
　　A.To introduce a new method of calculating blood alcohol levels.
　　B.To discover the relation between energy drinks and ABT test results.
　　C.To warn people of the dangers of drinking energy drinks.
　　D.To change the current legal alcohol limit for drivers in the United States.
　　参考答案：B
　　参考解析：细节理解题。根据文章第一段倒数第二句：“Can one of these energy drinks really cause someone to test positive on an ABT?Researchers in Missouri set up an experiment to find out.”可知，答案B符合文意。
　　5、Which of the following affects the ABT test result most for energy drink consumers?
　　A.The age of the person who takes the test.
　　B.The place where the test is given.
　　C.The equipment that the test uses.
　　D.The time when the test is taken.
　　参考答案：D
　　参考解析：细节理解题。根据文章最后一段中的“the test was given within one minute...15 minutes...This shows that when the test is taken plays an important role in the test result.The sooner the test is conducted after the consumption of these drinks，the more likely a positive alcohol reading will be obtained.”可知，在饮用功能性饮料多久之后进行测试会影响测试效果。
　　参考译文：
　　警察经常使用酒精呼气测试（abt）来判断一个人是否在开车时喝醉了。在美国，21岁或更大的人的法定血液酒精限值为0.08%，而21岁以下的人不允许驾驶体内含有任何酒精水平的车。“阳性”的测试结果，超过法律限制，允许警方逮捕司机。然而，许多在测试中呈阳性的人声称他们只喝了一种“不含酒精”的能量饮料。其中一种能量饮料真的能让人在ABT测试中呈阳性吗？密苏里州的研究人员建立了一个实验来找出答案。
　　首先，测量了27种流行能量饮料中的酒精含量，除了一种以外，其他所有饮料的酒精含量都大于0.005%，其中9种饮料的酒精含量至少为0.096%，然后，科学家们调查了ABT发现这些少量酒精的可能性，并要求受试者喝一杯。装满能量饮料的罐子或瓶子，然后在饮料喝完后给每个受试者一分钟15分钟。
　　对于27种能量饮料中的11种，如果在饮用后一分钟内进行测试，ABT没有发现酒精的存在。但是，如果在饮用后15分钟内进行测试，则任何一种饮料都不能发现酒精。这表明，当进行测试时，对测试结果起着重要的作用。他在饮用这些饮料后越早进行测试，就越有可能获得阳性的酒精读数。