A) actually I) likely B) consolidating J) monitored C) degrades K) participate D) deteriorates L) occasion E) excited M) perform F) extension N) recovery G) formation O) subsequently H) interested A research presented to the AAAS meeting in San Diego suggests that much of the world prefers to take a siesta (午睡) . It has already been established that those who take a siesta are less __36__to die of heart disease. Now, Matthew Walker and his colleagues at the University of California, Berkeley, have found that they probably have better memory, too. The role of sleep in __37__ memories that have already been created has been understood for some time. Dr. Walker has been trying to extend this understanding by looking at sleep’s role in preparing the brain for the __38__ of memories in the first place. He was particularly __39__ in a type of memory called episodic (不连贯的) memory, which relates to specific events, places and times. This contrasts with procedural memory, of the skills required to __40__ some sort of mechanical task, such as driving. The theory he and his team wanted to test was that the ability to form new episodic memories __41__ with accrued wakefulness, and that sleep thus restores the brain’s capacity for efficient learning. They asked a group of 39 people to __42__ in two learning sessions, one at noon and one at 6 p.m. On each __43__ the participants tried to memorize and recall 100 combinations of pictures and names. After the first session they were assigned randomly to either a control group, which remained awake, or a nap group, which had 100 minutes of _44__ sleep. Those who remained awake throughout the day became worse at learning. Those who napped, by contrast, __45__ improved their capacity to learn, doing better in the evening than they had at noon. These findings suggest that sleep is clearing the brain’s short-term memory and making way for new information.