单选题 Scientists say they now have proof to support the old-fashioned advice that it's best to sleep on a problem. They say sleep strengthens the memory and helps the brain organize the masses of information we receive each day.
Lead researcher Bob Stickgold at the Harvard Medical School said, "Sleep helps us draw rules from our experiences. It's like knowing the difference between dogs and cats, even if it's hard to explain. "
The US research team studied how well students remembered connections between words and symbols (象征), reports New Scientist. They compared how the students performed if they had had a sleep between seeing the words and having the test, and if they had not slept. They found that people were better able to remember lists of related words after a night's sleep than after the same time spent awake during the day. They also found it easier to remember themes (主题) that the words had in common. But they forgot around one in four more themes if they had been awake. Prof. John Groeger, of Surrey University's Sleep Research Centre, said, "People have been trying for years to find out what the purpose of sleep is, as we know that only certain parts of it have a restorative (有助恢复的) value. "
"We form and store huge numbers of experiences in the head every day, and sleep seems to be the way the brain deals with it all./

单选题 The phrase "to sleep on a problem" in Paragraph 1 most likely means to ______.

【正确答案】 B

【答案解析】[解析] 词句理解题。sleep on a problem是个习惯表达，本义指“把问题留到第二天解决”，此处作者实际上是用其引出短文主旨“睡眠”，因为这一表达中有sleep一词。而由该表达所在处的下一句sleep strengthens the memory and helps... (睡眠可以强化记忆并有助于大脑将我们每天接受到的大量信息组织起来)也可推知，睡觉有可能让人想出解决problem的办法，故本题答案是[B]。其余三项都明显不对。

单选题 In the study by the US research team, students were asked to ______.

【正确答案】 B

【答案解析】[解析] 细节题。对应的信息位于第三段第一句，该句明确指出研究的目的是测试how well students remembered connections between words and symbols(测试学生对单词及其象征意义之间联系的记忆程度)，其中的words and symbols就是指选项[B]中的words and their meanings。其余三项都与原文的说明不符。

单选题 Which of the following may be easier to remember?

【正确答案】 C

【答案解析】[解析] 分析推理题。短文第三段后半部分说明了研究的结果。其中第三、四、五句指出，睡一个晚上的觉后，学生们能更好地记住一些相关的单词，而拥有共同主题的那些单词则更容易记住。由于短文主旨就是睡眠的好处，故将这几句与选项对照后可知，正确答案是[C]。其余三项中，[A]属于用文中的个别词汇发挥而成，而[B]、[D]两项都属于原文没有提及的内容。

单选题 What may be the importance of the research?

【正确答案】 A

【答案解析】[解析] 分析推理题。推断的依据是短文最后两个直接引语。该处通过专家的话指出，人们一直想找出睡眠的目的(也就是作用)，而该研究发现睡眠似乎是大脑处理我们每天存储的大量经历(即信息)的方式，即试验表明睡眠有助于大脑处理信息(这与短文第一段第二句相互呼应)，这正是该试验的重要性所在，也是作者撰文说明这一实验的原因，故本题答案是[A]。其余三项都属于用原文中的词句设置的干扰项。