Everyone knows that a good sleep is important for our health.But not everyone knows how important it is to sleep in the dark.A new report says sleeping with the light on could be bad for our health.
    Researchers say turning off the light when we sleep helps us to keep away from diabetes（糖尿病）and heart disease.Sleeping with the light on could increase the risk of getting these diseases.The researchers said around 40 percent of people sleep with some kind of artificial（人造的）light.They said even light from a television or an alarm clock could be bad for our health.They added that the worst thing to sleep with is light.Sleeping in the dark is more difficult for people who live in cities，where there is a lot of outdoor light at night.
    The researchers are from the North western University Feinberg School of Medicine in Chicago，the USA.The lead researcher，Dr Phyllis Zee，is an expert in sleep medicine.She said it is healthier for us to turn off all lights when we sleep.Her team had a study of the blood sugar levels of 20 people after nights of sleep.①               Dr Zee said this is because light stimulates brain activity，which raises blood sugar levels.
    Dr Zee said there are some things we can do to solve the problem：turn off the lights，never sleep with white or blue light，use a blackout curtain or wear an eye mask.

（1）回答問題：Why is it more difficult for people who live in cities to sleep in the dark？

Because there is a lot of outdoor light there at night.

Because there is a lot of outdoor light there at night.

（2）List two ways we can do to make us sleep in the dark.
①

Turn off the lights and never sleep under white or blue light.

Turn off the lights and never sleep under white or blue light.

②

Use blackout curtains or wear eye masks.

Use blackout curtains or wear eye masks.

（3）Which of the following sentence can be put back into the blank①

A

A

？
A.The people who slept with the light on had higher blood sugar levels the next morning.
B.The blood sugar levels of the people who slept in complete darkness increased a lot.
（4）What does the underlined word " stimulates " mean in Chinese？

D

D

A.阻止
B.舒緩
C.減少
D.刺激
（5）The writer wrote the passage to tell us

not to sleep with the lights on

not to sleep with the lights on

.