About half American teenagers do not get enough sleep on school nights.They get an average

About half American teenagers do not get enough sleep on school nights.They get an average of sixty to ninety minutes less than experts say they need.
One reason for this is biology.Experts say teens are biologically programmed to go to sleep later and wake up later than other age groups.Yet many schools start classes as early as seven in the morning.As a result，many students go to class feeling like sixteenyearold Danny.He is an active teen— except in the morning.“Getting up in the morning is pretty terrible.I’m just very out of it and tired.Through the first and second period I can hardly stay awake,” he said.
Michael Breus is a psychologist.Teens，he says，need to sleep eight to nine hours or even nine to ten hours a night.He says sleepy teens can experience a form of depression(消沉) that could have big influence on their general well being.It can affect not just their ability in the classroom but also on the sports field and on the road.So what can schools do about sleepy students？The psychologist says one thing they can do is to start classes later in the morning.Studies show that students can improve by a full letter grade in their first and second period classes.
Eric Peterson is the head of St.George’s School in the northeastern state of Rhode Island.He wanted to see if a thirtyminute delay(推迟)would make a difference.It did.He says visits to the health center by tired students decreased by half.Late arrivals to the first period fell by a third.And students reported that they were less sleepy during the day.Eric Peterson knows that changing start times is easier at a small school like his.But he is hopeful that other schools will find a way.
【小题1】What’s the best title for the passage?A．Later classes，fewer sleepy teensB．Early birds have good foodC．Early to bed and early to riseD．Fewer classes，more happiness【小题2】The underlined word“this”in the second paragraph refers to .A．teenagers’ staying upB．teenagers’ getting up lateC．teenagers’ not getting enough sleepD．teenagers’ not studying seriously【小题3】Michael Breus thinks that .A．teens should get up earlyB．teens need enough sleep to be livelyC．depression is common in teensD．the first period class should be cut off【小题4】The last paragraph tells us .A．Eric Peterson visits the health center every dayB．it’s not easy for Eric Peterson to change start timesC．students in St.George’s School can get up later than beforeD．students in St.George’s School aren’t late for school any more【小题5】What can we infer from the passage?A．Danny is a lazy boy and always late for school.B．Teens should go to bed early and get up early, too.C．The psychologist has no idea how to solve the problem.D．Enough sleep makes a healthy and active student.A

(答案→)A 解析：本文讲述了美国的学生缺少睡眠，导致在学校上午的课程中表现较差，说明了充足睡眠的重要性。【小题1】A 主旨大意题。根据文章第一段About half American teenagers do not get enough sleep on school nights.They get an average of sixty to ninety minutes less than experts say they need.说明美国的学生缺少睡眠，导致上午前2节课的效果很差。故A正确。【小题2】C 推理题。本句One reason for this is biology.中的this就是指第一段中About half American teenagers do not get enough sleep on school nights.They get an average of sixty to ninety minutes less than experts say they need.提及的年轻人的睡眠不够情况。故C正确。【小题3】B 细节题。根据第二段6,7,8行Michael Breus is a psychologist.Teens，he says，need to sleep eight to nine hours or even nine to ten hours a night.He says sleepy teens can experience a form of depression(消沉) that could have big influence on their general well being.It can affect not just their ability in the classroom but also on the sports field and on the road可知缺少睡眠对年轻人有很大的影响，所以年轻人需要足够的睡眠让他们保持活跃。故B正确。【小题4】C 推理题。根据文章最后3行And students reported that they were less sleepy during the day.Eric Peterson knows that changing start times is easier at a small school like his.But he is hopeful that other schools will find a way.可知在这个学校里学生起床要比别的地方稍微晚一点。故C正确。【小题5】D 推断题。根据文章2,3段可知缺少睡眠会有很多问题，有了充足的睡眠可以让学生很健康积极向上。故D正确。

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