Everyone knows that the first rule of driving is never taking your eyes off the road. Teen drivers【C1】______being careful, but they tend to start multitasking after just a few months behind the wheel, according to research published Tuesday. And【C2】______older drivers can handle eating or talking to passengers, which【C3】______up the new drivers, dialing a cell phone increased the risk of accidents among young and【C4】______drivers alike. This isn't great news, since it's well【C5】______that distracted driving is a leading cause of accidents among all drivers. It makes sense that young drivers will start testing their limits after a few months behind the wheel, according to Bruce Simons-Morton, a behavioral scientist. "You increase the difficulty of a task until you make an【C6】______," Simons-Morton says. "It seems like a very natural thing but still it's very【C7】______, because good driving ability and safety judgment develops【C8】______a very long period of time." Within six months of getting their licenses, young drivers in this study -started texting, eating and【C9】______the radio while driving as much as their more skilled【C10】______But it takes thousands of hours of【C11】______to get good at driving, according to Simons-Morton. That disconnect may help【C12】______the high accident rates among teenage drivers. The researchers compared data from two small studies—one tracked 42【C13】______licensed young drivers and the other looked at 100 drivers with more experience . All the participants had sensors and cameras【C14】______in their cars. The researchers used the sensors to track when drivers got into accidents or close calls. The videos were then used to see what the drivers were doing just before the accidents【C15】______. Because the researchers wanted to focus on the【C16】______of distracted driving, they【C17】______crashes caused by drunk driving and ones that were clearly caused by other drivers. Since the number of people in this study was small, Simons-Morton says the results will have to be【C18】______by other research. A couple of bigger studies already【C19】______the works, might make things clearer. But Simons-Morton says this is the first totally【C20】______look at teen driver distraction.
单选题
【C1】
【正确答案】
C
【答案解析】解析：后半句表转折的but表明，teen drivers往往会在几个月后(after just a few months)就开始边开车边做其他事情(start multitasking)，这与being careful完全不同。由此判断，being careful是青少年刚开始开车时的表现。故选C项start off“开始”。
【答案解析】解析：which引导非限制性定语从句修饰前面的内容。开车时吃东西、和乘客讲话是老司机能应对的事，但对新手司机来说并非易事，trip up“使……犯错”能与新司机构成合理的动宾关系。且与下文increased the risk of accidents呼应。故选A项trip。
单选题
【C4】
【正确答案】
B
【答案解析】解析：空格处填入的形容词与young一起修饰drivers，alike表明对两种司机来说情况相似。dialing a cell phone相对于前半句老司机能轻松应对的eating or talking to passengers更难，因此不管是对于新司机还是老司机都是有风险的。因此B项experienced“有经验的”符合语义逻辑。
【答案解析】解析：上句提到Bruce Simons—Morton的观点是：有必要在开车后几个月内对对年轻司机进行极限测试(testing their limits)。本句即是对limits一词的具体解释。不断地增加任务的难度，直至犯错误，才能找到极限。故选C项error“错误”。
单选题
【C7】
【正确答案】
C
【答案解析】解析：but still表示语义转折，前面的a very natural thing表达肯定意义，所以本空格需填入含否定意义的形容词。根据常识可知，在青少年开车时不断地增加任务的难度(increase the difficulty of a task)是很危险的，故C项dangerous“危险的”。
单选题
【C8】
【正确答案】
D
【答案解析】解析：从句法上判断a very long period of time在句中应为“培养良好的驾驶能力和安全性判断”的时间状语。需要用介词引导。D项over表示时间时意为“在……期间”，后加时间段可表示“经过多长时间”，符合语义逻辑。
【答案解析】解析：as much as“像……一样”表比较，比较的双方分别是young drivers和their more skilled…上下文多次拿新老司机做比较，B项counterpart指“对应的人”，即司机，their more skilled counterpart意为“经验更丰富的司机”，符合本题语境。
单选题
【C11】
【正确答案】
D
【答案解析】解析：本句承接上文，表明Simons-Morton的观点，即要想有良好的驾驶技术，需要几千个小时的……。下文提到老司机时所用的表达是drivers with more experience。D项practice“实践”与experience(经验)语义呼应，故正确。
【答案解析】解析：所需介词和宾语the works搭配用于修饰主语A couple of bigger studies，这几个“更大规模的研究”应该已经在进行中才有可能弄清真相(might make things clearer)，故选D项in。in the works是固定搭配，表示“在进行中或准备中”。