2015年大学英语六级临考提分必做试卷（二）_第6页

　　Section C

　　Directions: In this section, you will hear a passage three times. When the passage is read for the first time, you should listen carefully for its general idea. When the passage is read for the second time, you are required to fill in the blanks numbered from 36 to 43 with the exact words you have just heard. For blanks numbered from 44 to 46 you are required to fill in the missing information. For these blanks, you can either use the exact words you have just heard or write down the main points in your own words. Finally, when the passage is read for the third time, you should check what you have written.

　　Sleep is part of a person's daily 36 cycle. There are several different stages of sleep and they occur in cycles, If you are an 37 sleeper, your sleep cycle is as follows. When you first drift off into slumber, your eyes will roll about a bit, your

　　38 will drop slightly, your 39 will relax, and your 40 will slow and become quite 41 Your brain waves slow down a bit too with the alpha rhythm of rather fast waves 42 for the first few minutes. This is called stage 1 sleep. For the next half hour or so as you relax more and more you will drift down through stage 2 and stage 3 sleep. The lower your stage of sleep the slower your brain waves will be. Then about 40 to 60 minutes after you lose 43 you will have reached the deepest sleep of all.

　　44. This is stage 4 sleep.

　　You do not remain at this deep fourth stage all night long, but instead about 80 minutes after you fall into slumber, your brain activity level will increase again slightly. The delta rhythm will disappear to be replaced by the activity pattern of brain waves. 45.

　　This period of rapid eye movement lasts for some ~ to 15 minutes and is called REM sleep. It is during REM sleep that most dreams seem to occur. 46 .You will slip gently back from stage I to 4.