题干

如图,在所给网格图(每小格均为边长是1的正方形)中完成下各题:(用直尺画图)

画出格点△ABC(顶点均在格点上)关于直线DE对称的△A1B1C1;在DE上画出点P,使PB+PC最小;在DE上画出点Q,使QA=QC.

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答案(点此获取答案解析)

解:如图,△A1B1C1即为所求;连接B1C,B1C与DE的交点即为点P;连接AC1,AC1与DE的交点即为所求点Q.

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阅读理解

    A new study of 8,000 young people in the Journal of Health and Social Behavior shows that although love can make adults live healthily and happily, it is a bad thing for young people. Puppy love(早恋)may bring stress for young people and can lead to depression. The study shows that girls become more depressed than boys, and younger girls are the worst of all.

    The possible reason for the connection between love and higher risk of depression for girls is “loss of self”. According to the study,even though boys would say “lose themselves in a romantic relationship”, this “loss of self” is much more likely to lead to depression when it happens to girls. Young girls who have romantic relationships usually like hiding their feelings and opinions. They won't tell that to their parents.

    Dr Marianm Kaufman,an expert on young people problems, says 15% to 20% young people will have depression during their growing. Trying romance often causes the depression. She advises kids not to jump into romance too early. During growing up, it is important for young people to build b friendships and a b sense of self. She also suggests the parents should encourage their kids to keep close to their friends, attend more interesting school activities and spend enough time with family.

    Parents should watch for signs of depression—eating or mood changes—and if they see signs from their daughters or sons, they need to give help. The good news is that the connection between romance and depression seems to become weak with age. Love will always make us feel young, but only maturity(成熟)gives us a chance to avoid its bad side effects.