Doctors have studied sleep for many years.It’s said that a lot happens when people sleep.It is reported that people have five stages (阶段) of sleep and that people may go through each stage every 90 minutes..
During the first two stages,you sleep lightly.That is ,if someone calls you or puts his hands on you,you wake up quickly.Your body rests quietly.Your heart beats slowly.you breathe (呼吸) more slowly than you are awake.
During Stages Three and Four,you sleep deeply.You don’t hear sound.Light doesn’t wake you up.Your heart beats more slowly than in Stages One and Two.The last stage of sleep is called Rapid Eye Movement.During REM sleep,you breathe faster,and your heart beats faster than in Stage One through Four.Your eyes move rapidly (快速地) under your eyelids (眼皮).All of this happens because you are dreaming.What doctors have proved (证明) is that everyone dreams..
（ ）1.The best title for this passage is __________.A.How to sleep
B.What is REM sleep C.Five stages of sleep D.The importance of sleep
( )2.During Stages One and Two,___________.A.we wake up easily.
B.we don’t want to wake up.C.we breathe quickly.D.We don’t wake up quickly.
( )3.When we sleep deeply,_________.A.we can hardly breathe.B.we can hear sounds
C.our hearts beat faster and faster D.neither sound nor light can wake us up easily
( )4.The Rapid Eye Movement shows that __________.A.we want to wake up B.we can hear someone calling C.our eyes are under our eyelids D.we are dreaming
( )5.Which of the following is true?A.Five stages of sleep usually takes90 minutes.B.You eyelids sometimes open during REM sleep.C.Sometimes we may go from the last stage of sleep to the first one.D.It is proved that we all dream during sleep.