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(2)连结AC、BC.因为BC的长度一定，所以△PBC周长最小，就是使PCPB?最小.B点关于对称轴的对称点是A点，AC与对称轴x=1的交点即为所求的点P.
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鞍不离马背，甲不离将 〖解释〗甲：铠甲。马不卸鞍，人不解甲。处于高度警惕状态。 鞍马劳神 见 鞍马劳顿 。 鞍前马后 马前马后。指追随左右。 鞍马之劳 鞍马：鞍子和马，指长途跋涉或打仗。形容旅途或战斗的劳苦。
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81.晏殊《浣溪沙》词上片 一曲新词酒一杯，去年天气旧亭台 ，两句构成 新 与 旧 的对 比，下片构成 来 与 去 对比的词句是：______________________，______________________。 82.白居易的《卖炭翁》中 可怜身上
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例题一：假设你叫刘京，是美国中学生托尼的笔友，你收到了他的来信。请给托尼写一封回信，回答他的问题，介绍北京良好的公交服务，并谈谈你的感受。 Hi! Liu Jing, My grandpa is going to Beijing next month beca
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Policemen were called by a shop in Southland early on Christmas morning. When they 1 they found two burglars (偷盗者) were kept in a lift with a heavy box of money. The two men were in their twenties
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中国古代著名诗人及风格(格式：作家 人生经历 思想内容 艺术特点) (1)王维 身陷叛军，皈依佛门 前期积极，后期求禅 诗中有画，画中有诗 人生经历：(公元701 761)，字摩诘，唐代山水田园诗人，原籍太原祁县(今属山西
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The water and the land are thought part of the earth surface (表面). The air is 1 thought a kind of blanket (毯子) 2 the earth. But it is 3 than that. Maybe you have been in a cave (洞穴) 4 in the ea
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如图，抛物线 经过A(-1，0)、C(0，4)两点，与x轴交于另一点B. (1)求抛物线的解析式; (2)已知点D(m，m 1)在第一象限的抛物线上，求点D关于直线BC对称的点的坐标; (3)在(2)的条件下，连接BD，点P为抛物线上一点，且 D
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如图，抛物线与x轴交于A，B两点，与y轴交于C点，且经过点(2，3a)，对称轴是直线x=1，顶点是M. (1)求抛物线对应的函数表达式; (2)经过C,M两点作直线与x轴交于点N，在抛物线上是否存在这样的点P，使以点P,A,C,N为顶点
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已知抛物线 (a=?0)经过点A(-2，0)，抛物线的顶点为D，过O作射线OM||AD .过顶点 D平行于x轴的直线交射线 OM于点C ，B在x 轴正半轴上，连结BC . (1)求该抛物线的解析式; (2)若动点P从点O出发，以每秒1个长度单位的速
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#p#分页标题#e#
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Debbie got up early last Saturday morning. She wanted 1 in Green Park with some of her friends. She was very 2 about it. 3 she was ready, she got on her bike and 4 for the park -- it was on the other
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It s over! Thank goodness! school was 1 and I was tired. I 2 at the front of the school bus. Janie, the driver, tries to 3 the uncomfortable atmosphere by striking the match of talks. I try to list
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21.陆游的《游山西村》中寓含哲理，广为流传的两句诗是：_______________________，_______________________。 22.《次北固山下》一诗中，表现时序变迁、新旧交替这一自然规律的诗句是：_______________________，_
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Why do people play football? It s a(n) 1 game and it s dangerous too. Twenty-two men fight 2 ninety minutes to make 3 many goals as they can. They get 4 black eyes, bruise (擦伤) and broken bones tha
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During the war, an English pilot (飞行员) was hurt. But he was 1 by a group of nuns (修女). He had been very 2 and lost his sense. When he came to himself he was 3 to find a woman beside him. It was
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要把一到 的英语单词复习一遍，把各单元的短语，语法总结归纳一下，重点课文要熟读，要背的背一背;找本语法书把初中学过语法过一遍，练听力，做习题。 对 时间 考察很多 听力似乎成了很多考生拿高分的拦路虎。建议
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每个学生，就都想成为优秀学生，肯定不会甘愿当一个 差生 。但是，在不知不觉中，你就被定格在 差生 的行列而不能自拔。以化学学科为例子，某一天，你突然感到：化学竟然这么难?!我听不懂! 其实，不是化学太难，而
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3l.大自然美丽的湖光山色涤荡了我们的心胸，让我们心清如水;愉悦了目鸟的性情，使它们在山林间尽情歌唱。这真是_______________________，_______________________。(填写常建《题破山寺后禅院》的诗句) 32. 李商隐
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Soon after Dave left university, one of his uncles, who was 1 and had no children of his own, died and 2 Dave a lot of money, so he decided to 3 his own company. He found a nice 4 , 5 some new furnit
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已知二次函数 。 (1)求证：不论a为何实数，此函数图象与x轴总有两个交点。 (2)设a
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Bob: In a book I was reading, some men had to 1 a desert. There was nothing 2 sand they could see. It was so large 3 it seemed to them that it had almost no 4 . Tom: It 5 be very hot. Bob: That s rig
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A thousand years ago, Hong Kong was covered by a thick forest. As more and more people came to 1 in Hong Kong, these trees were cut down and burnt. Now there is 2 forest left, though there are still
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Overhead bridges can be seen in many parts of Singapore, in the place where traffic is very heavy and crossing the road is 1 . These bridges can make people 2 roads safely. Overhead bridges are used
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如图，已知抛物线 经过A(1，0)，B(0，2)两点，顶点为D. (1)求抛物线的解析式; (2)将△OAB绕点A顺时针旋转90 后，点B落到点C的位置，将抛物线沿y轴平移后经过点C，求平移后所得图象的函数关系式; (3)设(2)中平移后，
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已知平行于x轴的直线 与函数y=x和函数y=1/x的图像分别交于点A和点B，又有定点P(2，0) . (1)若a
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如图，过△ABC的三个顶点分别作出与水平线垂直的三条直线，外侧两条直线之间的距离叫△ABC的 水平宽 (a)，中间的这条直线在△ABC内部线段的长度叫△ABC的 铅垂高(h) .我们可得出一种计算三角形面积的新方法： ，即
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When it was over 20 years ago, I first met Mr. Andrews, my old headmaster. During the war (战争) I was studying at school in the north of England. My 1 had just returned to London, and there were not
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Granny Sarya lived outside Moscow. Her only son 1 to Afghanistan(阿富汗) and was killed in action there.Soon after that, her husband lost his job. The old man was always 2 food and clothes.And on a w
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