When you first drift off into slumber,
your eyes will roll about a bit, your temperature will drop slightly, your
muscles will relax, and your breathing will become quite regular. Your brain
waves slow down a bit, with the alpha rhythm predominating for the first few
minutes. This is the first stage of sleep. For the next 30 minutes or so, you
will drift down through Stage 2 and Stage 3. The lower your stage of sleep, the
slower your brain waves will be. About 40-60 minutes after you lose
consciousness, you will reach the last stage. Your brain waves will show the
delta rhythm. You may think that you stay at this deep stage all the rest of the
night, but that turns out not to be the case. About 80 minutes after you fall
into slumber, your activity cycle will increase slightly. The delta rhythm will
disappear, to be replaced by the activity pattern of brain waves. Your eyes will
begin to dart around under your closed eyelids. This period of Rapid Eye
Movements lasts for 8-15 minutes and is called REM sleep.
During both light and deep sleep, the muscles in your body are relaxed but
capable of movement. As you slip into REM sleep, a very odd thing occurs -- most
of the voluntary muscles in your body become paralyzed. Although your brain
shows very rapid bursts of neural activity during REM sleep, your body is
incapable of moving. REM sleep is accompanied by extensive muscular inhibition.
单选题
On the part of an average sleeper, there______of sleep in cycles.
【正确答案】
D
【答案解析】[解析] 细节题型。
答案出自第一段第二到第六句Your brain waves slow down…for the first few minutes．This is the first stage of sleep…．you will reach the last stage．
单选题
When a person falls into the state of sleep, his______.
【正确答案】
A
【答案解析】[解析] 细节题型。
根据开篇第一句When you first drift off into slumber, your eyes’will roll about a bit…，正确答案应该是A。drift off into slumber“进入睡眠”。
单选题
The lower your stage of sleep,______.
【正确答案】
C
【答案解析】[解析] 细节题型。
参看第一段第五句The lower your stage of sleep, the slower your brain waves will be．
单选题
After you have reached the deepest sleep,______.
【正确答案】
C
【答案解析】[解析] 细节题型。
答案出自第一段的Your brain waves will show the delta rhythm. You may think that you stay at this deep stage…
单选题
In the REM sleep,______.
【正确答案】
D
【答案解析】[解析] 细节题型。
参看第一段的最后两句Your eyes will begin to dart around under your closed eyelids. This period of Rapid Eye Movements…is called REM sleep．
单选题
You will fall into the fourth stage of sleep______.
【正确答案】
C
【答案解析】[解析] 细节题型。
根据第一段第六句About 40-60 minutes after you lose consciousness, you will reach the last stage．得知答案。
单选题
The first paragraph of this passage tells us about______.
【正确答案】
C
【答案解析】[解析] 主旨题型。
第一段主要介绍了睡眠的四个阶段。
单选题
In this passage, the word "paralyzed" means unable to______.
【正确答案】
A
【答案解析】[解析] 词义题型。
从第二段第二句most of the voluntary muscles in your body become paralyzed中的voluntary可以推断paralyzed(瘫痪不能行动)是其反义词，另外，从最后两句中的incapable of moving和muscular inhibition也可以得到解释。
单选题
The phrase "extensive muscular inhibition" means______.