题干

已知椭圆C1
x
2
a
2
+
y
2
b
2
=1(a>b>0)的离心率为
3
2
,P(﹣2,1)是C1上一点.
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同类题2

阅读理解

    For some students, getting better grades can seem like an impossible task sometimes. With the challenges(挑战) of school, just paying attention in class or studying hard isn't always enough. But what if there were other ways for students to improve their grades? For parents and students who have ever wondered if this is possible, now you can rest easy. Research suggests that a person who likes doing activities can improve their grades.

    Scientists think that those students who are active are not just exercising their bodies, but also exercising their brains(大脑). In turn, they can be able to improve their grades at school.

    In the most recent study, researchers found that when children played for half an hour each day, they were better at organizing(组织) their schoolwork as well as doing project work and learning traditionally “difficult” subjects, such as maths.

    What does this mean for children who aren't active? Researchers think that if kids don't get enough activities, they are going to be at a disadvantage when it comes to school performance.

    In the research experiment, a group of children skipped with ropes(跳绳), played basketball and did a number of other games or exercises. Another group of children didn't do any activities. They took part in testing both before experiment and after the experiment. Testing was mainly for maths and reading skills. Results showed that the children in the activity group did better on the tests than those who had no activity.

    All work and no play will not only make Jack a dull(迟钝的) boy, but will also negatively(消极地) affect his grades in school, according to a new study published in the Journal of Pediatrics.

    Parents complain(抱怨) children today are actually less active and they always worry about their grades. Dr. Belton, an expert, said, “If you'd like to see your kids do better in school, have them close their books, set down their pencils and go outside to play.”

同类题5

阅读下列材料,根据提示回答问题

材料一: 是中国自由神,三民五权,推翻历史数千年专制之局。愿吾侪后死者,齐心协力,完成先生一二件未竞之功。                                   

——挽联

材料二:中国的土地可以征服而不可以断送!中国的人民可以杀戮而不可以低头!

——《北京学界全体宣言》

材料三:学联大会致电北京政府,要求誓死拒约,还电告参加巴黎和会的中国代表:“如违背民意……当与曹、章、陆同论!”

材料四:……军校的创办,是国共合作的产物,它为国共两党培养了许多军事将领和军事骨干,为东征、北伐战争和抗日战争的胜利做出了重要贡献……

——姜廷玉(军事博物馆研究员)

材料五:1927—1937年间,国民党各派军事集团的混战,特别是蒋介石发动的对红军的几次“围剿”,既给中国人民带来了无穷灾难,又给日本帝国主义发动大规模侵华战争以可乘之机。 

                                                          ——摘自《内战百科》

材料六:抗战精神的内涵是什么——从面对外来侵略,国难当头之际,全体中华儿女的一致抗日中体会到;从掩埋了牺牲战友,擦干脸上的泪水勇往直前的战斗中体会到;从面对日寇的疯

狂杀戮、血战到底的气势中体会到。