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1、.英语:Plants and animals, including humans, need food and water to live on. These are from the natural resources(资源) on Earth. To protect these resources, we need to keep the air clean and the water drinkable. We need to keep the soil (土壤)healthy. How do we do that?Protect the landThe soil that covers
2、 fields and farms provides much of the food we eat. Human activities such as plowing(耕) fields, mining(采矿), and building highways can destroy (破坏)the land. Erosion happen when wind and water carry away the soil. Soil erosion can turn rich farmland into a desert wasteland. So does this mean we should
3、nt build a highway or plow a field? Of course not. But it does mean we might think about Earthfriendly ways of doing those things.Today farmers plow their fields in different ways to prevent erosion. They try to use less water for their crops. They keep animals from eating the growing grass in just
4、one area. Farmers also plant trees to prevent erosion from happening.Save the TreesAnother human activity that damages the land is deforestation(采伐森林). People take away a large number of trees from a forest. Millions of square kilometers of forest disappear each year. When this happens, many plants
5、and animals lose their places to live. They may die out, or become very few. Scientists havent even discovered all the living things in the forest. We may be losing some without even knowing they are there. Trees absorb (吸收)and use carbon dioxide (二氧化碳)when they make food. Environmentalists encourag
6、e careful management of the forests. They ask people to replant trees after they cut down the forest. Recycle, Reuse, ReducePeople throw a piece of paper into the wastebasket after using it. The paper becomes trash. Where does the trash go next? Much of our trash ends up in landfills(垃圾填埋地). They ta
7、ke up valuable land and sometimes pollute the water, air, and land around them. More than a third of the trash in landfills is paper. Recycling, reusing, and reducing what you throw away can cut down on the need for more landfills. In fact, we can recycle about eighty percent of household trash.()1.
8、 What does the underlined word erosion mean?A. Plowing fields and miningB. Cutting down trees and farming.C. Wind and rain carrying away soil. D. Building highways on the farmland.()2. Why do we need to save the trees?A. To discover more new trees every year.B. To encourage careful management of the
9、 forest.C. To take away a large number of trees from the forest.D. To keep good places for animals and plants to live in.()3. How much of the trash can we recycle?A. All the trash.B. Very little. C. One third.D. Four fifths.根据对话内容,用方框中所给词的适当形式填空。teach, student, invent, himself, at, job, importance,
10、knowSchool education is very important and useful. Yet no one can learn everything at school and a teacher cannot teach his 1 everything they want to know.His 2 is to show his students how to learn. He teaches them how to read and how to think. So much more is to be learned outside school by the stu
11、dents 3 .It is always more 4 to know how to study by oneself. It is quite easy to learn something, but it is difficult to use it to solve problems. Great inventors do not get everything 5 school, but they still can 6 many things and change the world a lot.How can the inventors do all of this? One of
12、 the answers is: they 7 how to study. A lot of things are not taught in the classroom. They get a lot of knowledge by reading outside school. They work hard and never give up all their lives.科学:1.(2010年 桂林市30.6分) A、B、C、D、E是初中化学中的五种常见物质。C、D是单质,C为紫红色固体,D被认为是最清洁的能源。B的浓溶液常用做干燥剂。已知Fe和A、B的水溶液分别能发生反应:Fe +
13、A C + E; Fe + B D + E 。(1)写出A、B、C的化学式: A , B ,C 。(2)现有Fe和A、C三种固体组成的混合物,小刚想测定该混合物中C物质的质量分数,他设计并完成了以下实验:你认为,小刚的实验数据处理是否正确(填“正确”或“ 不正确”) ,理由是 。2.(2010年 乌鲁木齐市179分)物质发生化学变化的前后,总质量是否发生改变?是增加、减小还是不变呢?甲、乙、丙三位同学按下面的步骤进行探究:(1)提出假设:物质发生化学变化前后总质量不变。(2)设计并进行实验,甲设计的实验装置和选用药品如图A所示,乙设计的实验装置和选用药品如图B所示,他们在反应前后都进行了规范的
14、操作,准确的称量和细致的观察。写出A、B两个实验发生反应的化学方程式: , 。丙进行了图C所示的实验,在一根用细铜丝吊着的长玻璃棒两端,分别绕上粗铜丝,并使玻璃保持水平。然后,用酒精灯给a端铜丝加热数分钟。停止加热后冷却,他观察到的现象是 , 。(3)实验结论:甲认为:在化学反应中,生成物的总质量与反应物的总质量相等;乙、丙认为:在化学反应中,生成物的总质量与反应物的总质量不相等。(4)你认为 的结论正确,请从原子的角度分析,结论正确的理由是: 。(5)导致其他实验结论错误的原因是 , 。因此,如果 的反应,则一定要设计反应在密闭装置中进行。数学:(2009瑞安中考模拟第24题)如图甲,直角梯
15、形ABCD中,ADBC,BAD=B=90°,AD=AB=6cm,BC=8cm点E从点A出发沿AD方向以1厘米/秒的速度向终点D运动;点F从点C出发沿CA方向以2厘米/秒的速度向终点A运动当点E、F中有一点运动到终点时,另一点也随之停止设运动的时间为t秒(1)当t为何值时,AEF和ACD相似?(2)连接BF,随着点E、F的运动,四边形ABFE可能是直角梯形若可能,请求出t的值;若不能,请说明理由?(3)当t为何值时,AFE的面积最小,最小值是多少?英语:阅读:1. C 2. D 3. D 词汇:1. students 2. job 3. themselves 4. important 5. at 6. invent 7. know科学:1.(1)CuSO4 H2SO4 Cu (2)不正确 4.2g紫红色固体中包含有铁和硫酸铜反应生成的铜(铁和
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