【题目】Doctors sometimes use light therapy to treat a form of depression in people who get too little morning sun. But too much light at other times may actually cause such mood disorder. Long-lasting exposure to light at night brings depression, a new study finds, at least in animals.

The new data confirm observations from studies of people who work night shifts, says Richard Stevens of the University of Connecticut Health Center. Mood disorders join a growing list of problems, including cancer, obesity and diabetes that can occur when light throws life out of balance by disturbing the biological clock and its timing of daily rhythms.

In the new study, Tracy Bedrosian and Randy Nelson of Ohio State University exposed mice to normal light and dark cycles for four weeks. For the next four weeks, half of the mice remained on this schedule, and the rest received continuous dim light throughout their night. Compared with mice exposed to normal night-time darkness, those getting dim light at night lost their strong preference for sweet drinks. “A sign that they no longer get pleasure out of activities they once enjoyed,” Bedrosian says.

In a second test, mice were clocked on how long they actively tried to escape a pool of water. Those exposed to night lights stopped struggling and just floated in the water, a sign of “behavioral despair”, 10 times as long as the mice that had experienced normal night-time darkness. All symptoms of depression disappeared within two weeks of the mice returning to a normal light-dark cycle, the researchers report. The scientists could also quash the behavioral symptoms by injecting the brains of animals with a drug that prohibits the activity of certain molecules linked with human depression. This finding further suggests that light at night may cause something related to depression.

Human studies linking night-time light and mood disorders are important but can not easily detect molecular underpinnings(分子基础) as animal studies can, says George Brainard of Thomas Jefferson University. The new work, he says, suggests that the change of the biological clock by light at night can be “an extremely powerful force in regulating biology and behavior”.

【1After being exposed to continuous night-time light, the mice __________.

A. changed their preferences

B. escaped from the water more eagerly

C. remained active as before

D. showed less interest in their favorites

【2What does the underlined word “quash” in paragraph 4 probably mean?

A. study B. predict

C. ease D. cause

【3We can learn from the last paragraph that _______________.

A. light at night may have practical value

B. the biological clock is beneficial to humans

C. human mood disorders cannot be healed easily

D. human studies are more important than animal studies

【4What is the main idea of the passage?

A. Night-time light may cause depression.

B. A drug has been found to cure mood disorders.

C. The study on animals can be applied to humans.

D. Human biological clock can be controlled by light.

【题目】When Jane put out the idea of homeschooling to her parents, the first reaction they gave was, “You are cutting the child off the world.” “Did the child really get cut off or did the child socialize better?”

The moment we hear of homeschooling, we think the child will have no opportunities to interact with their peers. However, in my friend’s opinion, we forget that when attending a regular school, the child is not into socializing all the while. The child is restricted to so many other activities. Studies take a major role in a child’s life. The child hardly has the time to interact at school.

The child might be meeting and studying along with many peers; however, how many kids interact with all the kids in a class? But in homeschooling system, as my friend mentioned, the kid has all the time and can plan his day accordingly. During the day the child studies just like other school-going kids but with no burden of homework and project work, the child has so much free time in the evening as to effectively interact and play with peers. The quality time the child spends in education is really impressive.

Homeschooled kids have the opportunity to socialize more often as they have a lot of time in their hands. They can also make socializing a regular habit. Just as my friend said, her child goes to a neighboring park almost every day and has a set of friends who go there daily. Other children get back home to finish off homework and project work whereas her child who is already through with studies gets the opportunity to spend time with family members.

When I heard this, I really felt how lucky the child was. Definitely the child had a better opportunity to socialize when compared with my kid. However, I might not consider homeschooling for my kid, as I am so used to the conventional schooling system and feel regular schooling the safest bet.

1The author’s purpose in writing the passage is to _________.

A. express his views on homeschooling

B. explain what homeschooling is

C. share his ways of teaching his children

D. promote homeschooling

2What is the biggest advantage of homeschooled children?

A. They will become braver.

B. They can be more popular.

C. They can socialize better.

D. They will know how to arrange time.

3What do we know about homeschooled children?

A. They don’t interact with their peers often.

B. They have more spare time to play.

C. They are restricted to certain activities

D. They can’t gain enough knowledge.

4How does the passage mainly develop?

A. By following the order of importance.

B. By following the order of time.

C. By making comparisons.

D. By presenting data.

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