After a day of work and play, the body needs to rest. Sleep is necessary for good health.
There are four levels of sleep, each being a little deeper than the one before. As you sleep, your muscles relax little by little. Your heart beats more slowly, and your brain slows down. After you reach the fourth level, your body shifts back and forth from one level of sleep to another. Although your mind slows down, from time to time you will dream. Scientists who study sleep state that when dreaming occurs, your eyeballs begin to move quickly (although your eye-lids are closed). This stage of sleep is called REM, which stands for rapid eye movement.
If you have trouble falling asleep, some people recommend breathing very slowly and very deeply. Other people believe that drinking warm milk will help make you drowsy. There is also an old suggestion that counting sheep will put you to sleep.
A good title for this passage is______.
A.Sleep
B.Good Health
C.Dreams
D.Work and Rest