多项选择题

下列选项中，关于图线的说法，正确的有（）。

A.虚线、单点长画线或双点长画线的线段长度和间隔，宜各自相等
B.单点长画线的两端，可以是点
C.单点长画线或双点长画线，当在较小图形中绘制有困难时，可用实线代
D.同一张图纸内，相同比例的各图样，应选用相同的线宽组
E.相互平行的图线，其间隙不宜小于其中的粗线宽度，且不宜小于0.7mm

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For this part, you are allowed 30 minutes to write a short essay entitled What 3G Brings to the Campus. You should write at least 120 words following the outline given below.1．3G网络的建设和使用让手机又有了新的功能2．3G手机是否会快速进入校园3．面对日益更新的手机技术，在校生应该采取什么样的态度What 3G Brings to the Campus

A.B.3G网络的建设和使用让手机又有了新的功能
C.3G手机是否会快速进入校园
D.面对日益更新的手机技术，在校生应该采取什么样的态度

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Stress in CollegeMost students in US colleges are just plain stressed out, from everyday worries about grades and relationships to darker thoughts of suicide, according to a poll of undergraduates from coast to coast. The survey was conducted for the Associated Press and MFVU, a television network available at many colleges and universities.Students' Stress ProblemFour in 10 students say they endure stress often. Nearly one in five say they feel it all or most of the timE.But most are bearing it. Nearly 60% in the survey say they enjoy lifE.The majority cite classic stress symptoms including trouble concentrating, sleeping and finding motivation. Most say they have also been disturbed, worried, too tired to work. 'Everything is being piled on at once,' said Chris Curran, a junior at the Albany College of Pharmacy (制药) in Albany, N.Y. tie said he has learned to cope better since starting school. 'You just get really disturbed and anxious. Then you start procrastinating (拖延), and it all piles up.' Many cite eating problems and say they have felt lonely, depressed, like they are failures. Substantial numbers are even concerned about spring break, chiefly not having enough money or being in good physical shapE.More than a quarter of the students sometimes think they should cut down on drinking or going out. A third say they, sometimes want to use drugs or alcohol to relax. About 15% say they're at least somewhat concerned about drinking too much on spring break. One in five say they have felt too stressed to do schoolwork or be with friends. About the same number say things have been so bad ill the past three months that they have seriously considered dropping out of school. Darker still, about one in six say they have friends who in the past year have discussed committing suicide, and about one in 10 say they have seriously considered it themselves. Friends have actually tried to end their lives in that time, one in 10 say. In this ocean of campus anxiety, 13% say they have been diagnosed with a mental health condition such as depression or an anxiety disorder.Of that group, two-thirds say they always or usually follow their treatment, one-tenth say they have been unable to stick to it, and the rest are not on a plan. The perils (危险) of halting treatment were highlighted last month when police said the girlfriend of Steven Kazmierczak, who fatally shot five people and then himself at Northern Illinois University, told them he had stopped taking medication. Six in 10 in the survey say they are usually hopeful and enjoy lifE.Half even concede they feel understood by their families.What Causes the Stress ProblemEven so, the survey shows plenty of sources of stress, led by the seven in 10 students who attribute it to school work and grades. Financial problems are close behind, while relationships and dating, family problems and extracurricular activities all are named by half as adding pressurE.College women have a more stressful existence than men, with 45% of females and 34% of males saying they face pressure often. The youngest students cite frequent stress most often. Whites report more stress than blacks and Hispanics. From schoolwork to dating, women are more possible than men to say they experience pressure from virtually every potential source of distress in the survey. Six in 10 women and just four in 10 men say family issues cause problems, though the differences between the sexes in most areas are slimmer. Besides balancing her approaching graduation with the 20-hour-per-week job that helps finance school, Jeanette Devereaux-Weber said she has a new pressure: beginning her post-college lifE.She has not decided what to do.' It doesn't feel like looking for a summer job anymore, it's looking for a career, it's things that will shape everything to come,' she saiD.'Sometimes it feels likeA.a TV stationB.a universityC.a radio stationD.a television network

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