The Secrets of Sleep
Have you ever wondered why you spend so much of your life asleep? Just as electricity charges the battery of a mobile phone, sleep recharges your body and your mind.
What is sleep?
Why do people need to sleep?
Humans could not function without sleep. According to the Royal College of Paediatrics and Child Health, sleep helps people learn by strengthening their memories. It has physical benefits too—like maintaining a healthy weight and boosting your immune system.
What are dreams?
Dreams usually occur during a stage of sleep known as rapid eye movement (REM) sleep. In REM, the eyes move quickly back and forth and brain activity increases. Scientists are not sure why people dream.
How much sleep do I need?
Most adults need around eight hours of sleep a day, but Mandy Gurney, who runs the Millpond Children’s Sleep Clinic, says that children need more.
A.When I wake up, I am reborn. |
B.I really think I need more sleep than now. |
C.Sleep is a natural and temporary state of rest. |
D.Some say it is a process that helps store memories. |
E.Too little sleep can make you tired and bad-tempered. |
F.You become healthier and thus diseases will not bother you. |
G.Sleep is more vital for children because their minds and bodies are still developing. |

同类型试题

y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2


y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2

