2教案全等三角形教师版

2024-06-28

2教案全等三角形教师版（共7篇）

2教案全等三角形教师版篇1

2.全等三角形

知识考点：

掌握用三角形全等的判定定理来解决有关的证明和计算问题，灵活运用三角形全等的三个判定定理来证明三角形全等。精典例题：

【例1】如图，已知AB⊥BC，DC⊥BC，E在BC上，AE＝AD，AB＝BC。求证：CE＝CD。分析：作AF⊥CD的延长线（证明略）

评注：寻求全等的条件，在证明两条线段（或两个角）相等时，若它们所在的两个三角形不全等，就必须添加辅助线，构造全等三角形，常见辅助线有：①连结某两个已知点；②过已知点作某已知直线的平行线；③延长某已知线段到某个点，或与已知直线相交；④作一角等于已知角。

AFDA34E1A12CEBBD2PCBEC例1图

例2图

问题一图

【例2】如图，已知在△ABC中，∠C＝2∠B，∠1＝∠2，求证：AB＝AC＋CD。

分析：采用截长补短法，延长AC至 E，使AE＝AB，连结DE；也可在AB上截取AE＝AC，再证明EB＝CD（证明略）。探索与创新：

【问题一】阅读下题：如图，P是△ABC中BC边上一点，E是AP上的一点，若EB＝EC，∠1＝∠2，求证：AP⊥BC。

证明：在△ABE和△ACE中，EB＝EC，AE＝AE，∠1＝∠2 ∴△ABE≌△ACE（第一步）

∴AB＝AC，∠3＝∠4（第二步）∴AP⊥BC（等腰三角形三线合一）

上面的证明过程是否正确？若正确，请写出每一步的推理依据；若不正确，请指出关键错在哪一步，并写出你认为正确的证明过程。

略解：不正确，错在第一步。

正确证法为：∵BE＝CE∴∠EBC＝∠ECB 又∵∠1＝∠2∴∠ABC＝∠ACB，AB＝AC∴△ABE≌△ACE（SAS）∴∠3＝∠4又∵AB＝AC∴AP⊥BC 评注：本题是以考查学生练习中常见错误为阅读材料设计而成的阅读性试题，其目的是考查学生阅读理解能力，证明过程中逻辑推理的严密性。阅读理解题是近几年各地都有的新题型，应引起重视。

【问题二】众所周知，只有两边和一角对应相等的两个三角形不一定全等，你能想办法安排和外理这三个条件，使这两个三角形全等吗？

请同学们参照下面的方案（1）导出方案（2）（3）（4）。

解：设有两边和一角对应相等的两个三角形，方案（1）：若这个角的对边恰好是这两边中的大边，则这两个三角形全等。方案（2）：若这个角是直角，则这两个三角形全等。方案（3）：若此角为已知两边的夹角，则这两个三角形全等。

评注：这是一道典型的开放性试题，答案不是唯一的。如方案（4）：若此角为钝角，则这两个三角形全等。（5）：若这两个三角形都是锐解（钝角）三角形，则这两个三角形全等。能有效考查学生对三角形全等概念的掌握情况，这类题目要求学生依据问题提供的题设条件，寻找多种途径解决问题。本题要求学生着眼于弱化题设条件，设计让命题在一般情况不成立，而特殊情况下成立的思路。跟踪训练：

一、填空题：

1、若△ABC≌△EFG，且∠B＝60，∠FGE－∠E＝56，则∠A＝度。

2、如图，AB∥EF∥DC，∠ABC＝90，AB＝DC，那么图中有全等三角形对。

3、如图，在△ABC中，∠C＝90，BC＝40，AD是∠BAC的平分线交BC于D，且DC∶DB＝3∶5，则点D到AB的距离是。

AEDAA0

EHDCBFCCDBB第4题图第3题图第2题图

4、如图，在△ABC中，AD⊥BC，CE⊥AB，垂足分别为D、E，AD、CE交于点H，请你添加一个适当的条件：，使△AEH≌△CEB。

5、如图，把一张矩形纸片ABCD沿BD对折，使C点落在E处，BE与AD相交于点O，写出一组相等的线段（不包括AB＝CD和AD＝BC）。

6、如图，∠E＝∠F＝90，∠B＝∠C，AE＝AF。给出下列结论：①∠1＝∠2；②BE＝CF；③△ACN≌△ABM；④CD＝DN。其中正确的结论是（填序号）。

二、选择题：

1、如图，AD⊥AB，EA⊥AC，AE＝AD，AB＝AC，则下列结论中正确的是（）A、△ADF≌△AEG B、△ABE≌△ACD C、△BMF≌△CNG D、△ADC≌△ABE 0EDAFMGEEAODCMD1ABC2FNBBC填空第5题图

填空第6题图选择第1题图

02、如图，AE＝AF，AB＝AC，EC与BF交于点O，∠A＝60，∠B＝25，则∠EOB的度数为（）A、60 B、70 C、75 D、85

3、如果两个三角形的两边和其中一边上的高分别对应相等，那么这两个三角形的第三边所对的角（）A、相等 B、不相等 C、互余 D、互补或相等

EAFOCBAP0

BCD选择第2题图选择第4题图

4、如图，在△ABC中，AD是∠A的外角平分线，P是AD上异于A的任意一点，设PB＝m，PC＝n，AB＝c，AC＝b，则(mn)与(bc)的大小关系是（）

A、mn＞bc B、mn＜bc

C、mn＝bc D、无法确定

三、解答题：

1、如图，∠1＝∠2，∠3＝∠4，EC＝AD。求证：△ABE和△BDC是等腰三角形。

D4E31AB2CFDBACE解答题第1题图

解答题第2题图

2、如图，AB＝AE，∠ABC＝∠AED，BC＝ED，点F是CD的中点。（1）求证：AF⊥CD；

（2）在你连结BE后，还能得出什么新结论？请再写出两个。

3、（1）已知，在△ABC和△DEF中，AB＝DE，BC＝EF，∠BAC＝∠EDF＝100，求证：△ABC≌△DEF；（2）上问中，若将条件改为AB＝DE，BC＝EF，∠BAC＝∠EDF＝70，结论是否还成立，为什么？

4、如图，已知∠MON的边OM上有两点A、B，边ON上有两点C、D，且AB＝CD，P为∠MON的平分线

0上一点。问：（1）△ABP与△PCD是否全等？请说明理由。

（2）△ABP与△PCD的面积是否相等？请说明理由。

BAPOCDNMCFAEBD解答题第4题图解答题第5题图

5、如图，已知CE⊥AB，DF⊥AB，点E、F分别为垂足，且AC∥BD。

（1）根据所给条件，指出△ACE和△BDF具有什么关系？请你对结论予以证明。（2）若△ACE和△BDF不全等，请你补充一个条件，使得两个三角形全等，并给予证明。

参考答案

一、填空题：

1、32；

2、3；

3、15；

4、AH＝BC或EA＝EC或EH＝EB等；

5、DC＝DE或BC＝BE或OA＝OE等；

6、①②③

二、选择题：BBDA

三、解答题：

1、略；

2、（1）略；（2）AF⊥BE，AF平分BE等；

3、（1）略；（2）不成立，举一反例即能说明；

4、（1）不一定全等，因△ABP与△PCD中，只有AB＝CD，而其它角和边都有可能不相等，故两三角形不一定全等。（2）面积相等，因为OP为∠MON平分线上一点，故P到边AB、CD上的距离相等，即△ABP中AB边上的高与△PCD中CD边上的高相等，又根据AB＝CD（即底边也相等）从而△ABP与△PCD的面积相等。

5、（1）△ACE和△BDF的对应角相等；（2）略

全等三角形教案篇2

教材内容分析：

本节课内容是全章学习的开篇课，也是本章学习的主线，主要介绍全等三角形的概念和性质。通过对生活中的全等图形和抽象的几何图形的观察，使学生对全等有一个感性的认识，建立对应的概念，掌握寻找全等三角形中对应元素的方法，理解全等三角形的性质，为学习判定两个三角形全等以及第十六章轴对称图形提供了必要的理论基础。

全等三角形中严密的对应关系能够锻炼学生的观察力和推理能力，对它的深入研究有助于学生理解数学的本质，提升思维水平。

教学目标：

1.了解全等形、全等三角形的概念；理解全等三角形的性质； 2.能够准确找出全等三角形的对应元素，逐步培养学生的识图能力；

3.让学生通过观察生活中的全等形和动手操作获得全等三角形的体验，在探究和运用全等三角形性质的过程中感受到数学活动的乐趣。

教学重难点及突破：

重点：全等三角形的概练和性质；

难点：能在全等变换中准确找到对应角、对应边。

教学突破：通过生活中的实例观察、感受全等形和全等三角形，动手操作、合作交流，亲身体验创造全等三角形，加深全等三角形的有关概念的理解。

教学准备：

1.教师准备：多媒体课件、剪刀、白纸等； 2.学生准备：白纸、剪刀等。

教学流程：创设情境，引入新知→合作交流，探索新知→手脑并用，理解新知→合作交流，应用新知→课堂练习，巩固新知→师生互动，小结新知。

教学过程设计：

一、创设情境，引入新课。

1、与学生谈话，努力走近学生之中。

2、游戏情景，引入新课出示课件：大家来找茬游戏

引导：

1、观察两副图形在形状、大小、位置方面的共同点

2、两副图形形状、大小若相同该如何检验？

引导：什么样的图形叫做全等形？

定义：能够完全重合的两个图形叫做全等形；列举生活中的实例（一百元人民币）感知全等形。

二、合作交流，探索新知。

1、手脑并用，感受新知

用剪刀在一张纸上剪出两个形状、大小完全一样的三角形，引出全等三角形教学。

2、观察诱导，探究新知。（1）全等三角形相关概念

引导观察：课件操作演示两个三角形完全重合。引导学生类比得出全等三角形定义；

中国人民邮政

能够完全重合的两个三角形叫做全等三角形引导学生概括对应顶点、对应边、对应角定义；

全等三角形中，互相重合的顶点叫对应顶点.互相重合的边叫对应边.互相重合的角叫对应角。

（2）全等三角形的表达式

引导学生书写全等三角形的表达式：△ABC≌△DEF，读作：△ABC全等于△DEF。

温馨提示：

①记两个三角形全等时，通常把表示对应顶点的字母写在对应的位置上。②全等符号“≌”中“∽”表示形状相同，“=”表示大小相等，合起来就是形状相同、大小相等，即全等。

引导学生感悟：三角形全等表达式充分体现出数学的秩序性和精确性，使用规范的表达式将有助于解决相关的问题

（3）全等三角形性质

引导学生观察并概括全等三角形性质

全等三角形的性质：全等三角形的对应边相等，对应角相等。用几何语言表达全等三角形性质： ∵△ABC≌△DEF(已知)∴AB=DE，AC=DF，BC=EF；

∠A=∠D，∠B=∠E，∠C=∠F（全等三角形的对应边相等，对应角相等）

3、合作交流，探究新知（1）手脑并用，体验新知

利用刚才剪下的两个全等三角形，在课桌上摆出不同形状的图形，再与同伴合作交流，探究如何通过操作其中一个三角形使它们再次重合？

通过课件展示引导学生理解只要两个三角形的形状大小相同，不管位置怎样变化，都能通过平移旋转翻折的方式使之重合。

（2）观察交流，探究新知

引导学生观察，交流探索规律。在全等三角形中，一般是： 1．有公共边，则公共边为对应边； 2．有公共角，则公共角为对应角；

3．最大边与最大边（最小边与最小边）为对应边；最大角与最大角（最小角与最小角）为对应角；

引导学生观察，交流发现规律。

针对所得的对应角、对应边情况引导学生总结：规范地写出全等三角形表达式具有重要的意义，根据表达式中字母的对应情况就能够，准确判断出全等三角形的对应顶点、对应边、对应角。

三、合作交流，应用新知。

例：如图，△ABO≌△DCO，指出所有的对应边和对应角。

解：∵△ABO≌△DCO(已知)∴AB=DC，BO=CO，AO=DO（全等三角形的对应边相等）

∠A=∠D，∠ABO=∠DCO，∠AOB=∠DOC（全等三角形的对应角相等）变式：若上图中△ABC≌△DCB，试写出这两个三角形中相等的边和相等的角。

解： ∵△ABC≌△DCB(已知)∴AB=DC，BC=CB，AC=BD（全等三角形的对应边相等）

∠A=∠ D，∠ABC=∠DCB，∠ACB=∠DBC（全等三角形的对应角相等）

四、课堂练习，巩固新知。

（1）如图,△ABD≌△EBC，AB=3cm,BC=5cm, 求DE的长.解：∵△ABD≌△EBC，且AB=3cm,BC=5cm（已知）

∴AB=EB=3cm，BC=BD=5cm（全等三角形的对应边相等）∴DE=BD-EB=5-3=2cm

（2）如图，已知△ABC≌△ADE, 想一想: ∠ BAD= ∠ CAE吗?为什么?

解:相等，∵△ABC≌△ADE(已知)∴∠BAC=∠DAE(全等三角形对应角相等)∴∠BAC—∠DAC=∠DAE—∠DAC(等式性质)即∠BAC=∠DAE

五、师生互动，小结新知。

学习了这堂课你有哪些收获？并把它与同伴一起分享。

1、全等形的定义：能够完全重合的两个图形，叫做全等形。

2、全等三角形的定义：能够完全重合的两个三角形叫做全等三角形。

3、全等三角形的性质：全等三角形对应边相等，对应角相等。

4、寻找全等三角形的对应边、对应角得规律。（1）观察图形特点；

（2）观察表达式（对应关系）

六、布置作业。

课本P92习题15.1，第2、4题。

七、教后感

······

板书设计：

15.1 全等三角形

定义：

表示性质：

全等三角形优秀教案篇3

利用教科书提供的素材和活动，鼓励学生经历观察、操作、推理、想象等活动，发展学生的空间观念，体会分析问题、解决问题的方法，积累数学活动经验。培养学生有条理的思考，表达和交流的能力，并且在以直观操作的基础上，将直观与简单推理相结合，注意学生推理意识的建立和对推理过程的理解，能运用自己的方式有条理的表达推理过程，为以后的证明打下基础。

学情分析

学生通过前面的学习已了解了图形的全等的概念及特征，掌握了全等图形的对应边、对应角的关系，这为探究三角形全等的条件做好了知识上的准备。另外，学生也具备了利用已知条件作三角形的基本作图能力，这使学生能主动参与本节课的操作、探究成为可能。

教学目标

（1）学生在教师引导下，积极主动地经历探索三角形全等的条件的过程，体会利用操作、归纳获得数学结论的过程。

（2）掌握三角形全等的“边边边”、“边角边”、“角边角”、“角角边”的判定方法，了解三角形的稳定性，能用三角形的全等解决一些实际问题。

（3）培养学生的空间观念，推理能力，发展有条理地表达能力，积累数学活动经验。

教学重点和难点

重点：三角形全等条件的探索过程是本节课的重点。

从设置情景提出问题，到动手操作，交流，直至归纳得出结论，整个过程学生不仅得到了两个三角形全等的条件，更重要得是经历了知识的形成过程，体会了一种分析问题的方法，积累了数学活动经验，这将有利于学生更好的理解数学，应用数学。

难点：三角形全等条件的探索过程，特别是创设出问题后，学生面对开放性问题，要做出全面、正确得分析，并对各种情况进行讨论，对初一学生有一定的难度。

根据初一学生年龄、生理及心理特征，还不具备独立系统地推理论证几何问题的能力，思维受到一定的局限，考虑问题不够全面，因此要充分发挥教师的主导作用，适时点拨、引导，尽可能调动所有学生的积极性、主动性参与到合作探讨中来，使学生在与他人的合作交流中获取新知，并使个性思维得以发展。

教学过程

一、回顾概念整合知识以提问的方式引出本节课的教学内容：

问题1通过调查你对商品的标价、售价、进价和利润、利润率这些概念清楚了吗？你能列出它们之间的关系式吗？

（学生板书写出三个基本关系式）

教师引导得出变形关系式：利润＝进价 × 利润率。

设计意图通过调查使学生对商品销售过程所涉及的基本量、基本关系式有初步的了解，为后续的学习作好铺垫。

二、强化练习巩固概念

问题2运用基本关系式来做一组练习．

1．如果足球的进价是每个a元，超市按进价提高30％后标价，则标价是多少元？

2．如果足球的进价是每个a元，标价是每个150元，现7折优惠，则每个足球的利润是多少元？

3．如果足球的进价是每个a元，卖出后盈利25％，则每个足球的利润是多少？

4．如果足球的进价是每个a元，卖出后亏损25％，则每个足球的利润是多少？

设计意图通过题组练习使学生熟练掌握进价、标价、利润、利润率之间的关系，进而促使学生理解概念。

三、实践应用合作交流

问题3解决调查编写的商品销售方面的有关问题。

设计意图通过让学生编题互问互检，学生间的.相互评价，拓展学生思维，给学生创造一个合作交流和表现发挥的舞台，让学生充分体验成功后的喜悦。

四、联系实际探究新知

问题4某商店在某一时间以每件60元的价格卖出两件衣服，其中一件盈利25％，另一件亏损25％，卖这两件衣服总的是盈利还是亏损，或是不盈不亏？

教师在学生独立思考几分钟后让学生估算并简单说出估算的理由，估算对否不给予评判，告诉学生估算对不对还要进行计算。如何计算学生先独立思考，然后同桌交流，最后请一名同学到黑板板演利用一元一次方程解决此实际问题全部过程，其他同学在底下完成。完成后同学间相互评价。最后教师指出解决问题的关键——寻找等量关系，教师再进一步用估算方法分析亏损的原因。

设计意图在学生基本掌握解决有关商品销售问题的基础上对所学内容进行拓展，延伸。设计开放性问题的目的是通过本题的讲解使学生灵活运用本节的知识解决生活中的实际问题，也使全体学生在获得必要发展的前题下，不同的学生获得不同的体验。

五、巩固练习当堂反馈

问题5若某商品因库存积压，准备打折出售，如果按定价的7.5折出售将赔25元，而按定价的9折出售将赚20元．该商品定价是多少元？

（同学们思考后各自独立完成，然后同学互判）设计意图本节课对学生来说是一个难点，因此设计反馈这一环节很有必要，便于教师掌握学生学习的情况。

六、布置作业课后延伸

2教案全等三角形教师版篇4

[教学目标]

〔知识与技能〕

理解三角形的外角；

2、掌握三角形外角的性质，能利用三角形外角的性质解决问题。〔过程与方法〕

在观察、操作、推理、归纳等探索过程中，发展学生的合情推理能力，逐步养成数学推理的习惯

〔情感、态度与价值观〕

体会数学与现实生活的联系，增强克服困难的勇气和信心

[重点难点] 三角形的外角和三角形外角的性质是重点；理解三角形的外角是难点。[教学过程]

一、导入新课

〔投影1〕如图，△ABC的三个内角是什么？它们有什么关系？是∠A、∠B、∠C，它们的和是1800。

若延长BC至D，则∠ACD是什么角？这个角与△ABC的三个内角有什么关系？二、三角形外角的概念

∠ACD叫做△ABC的外角。也就是，三角形一边与另一边的延长线组成的角，叫做三角形的外角。

想一想，三角形的外角共有几个？共有六个。

注意：每个顶点处有两个外角，它们是对顶角。研究与三角形外角有关的问题时，通常每个顶点处取一个外角.三、三角形外角的性质

容易知道，三角形的外角∠ACD与相邻的内角∠ACB是邻补角，那与另外两个角有怎样的数量关系呢？

〔投影2〕如图，这是我们证明三角形内角和定理时画的辅助线，你能就此图说明∠ACD与∠A、∠B的关系吗？

∵CE∥AB，∴∠A=∠1，∠B=∠2 又∠ACD=∠1+∠2 ∴∠ACD=∠A+∠B 你能用文字语言叙述这个结论吗？

三角形的一个外角等于与它不相邻的两个内角之和。由加数与和的关系你还能知道什么？

三角形的一个外角大于与它不相邻的任何一个内角。即

ACDA，ACDB。

四、例题

〔投影3〕例

如图，∠

1、∠

2、∠3是三角形ABC的三个外角，它们的和是多少？

分析：∠1与∠BAC、∠2与∠ABC、∠3与∠ACB有什么关系？∠BAC、ABC、∠ACB有什么关系？

解：∵∠1+∠BAC=1800，∠2+∠ABC=1800，∠3+∠ACB=1800，∴∠1+∠BAC+∠2+∠ABC+∠3+∠ACB=5400

又∠BAC+∠ABC+∠ACB=1800

∴∠1+∠2+∠3==3600。

你能用语言叙述本例的结论吗？三角形外角的和等于3600。

五、课堂练习课本15頁练习；

六、课堂小结

1、什么是三角形外角？

2、三角形的外角有哪些性质？

七、作业：

课本12頁5、6；

2教案全等三角形教师版篇5

全等三角形的证明专题训练三角形全等的条件

1、三组对应边分别相等的两个三角形全等(简称SSS或“边边边”)，这一条也说明了三角形具有稳定性的原因。

2、有两边及其夹角对应相等的两个三角形全等(SAS或“边角边”)。

3、有两角及其夹边对应相等的两个三角形全等(ASA或“角边角”)。由3可推到

4、有两角及一角的对边对应相等的两个三角形全等(AAS或“角角边”)

5、直角三角形全等条件有：斜边及一直角边对应相等的两个直角三角形全等(HL或“斜边，直角边”)

所以，SSS,SAS,ASA,AAS,HL均为判定三角形全等的定理。

注意：在全等的判定中，没有AAA和SSA，这两种情况都不能唯一确定三角形的形状。

专题训练

一、选择题：

1.能使两个直角三角形全等的条件是()

A.两直角边对应相等C.两锐角对应相等B.一锐角对应相等 D.斜边相等 B.AB4，BC3，A30 D.C90，AB6 2.根据下列条件，能画出唯一ABC的是()A.AB3，BC4，CA8 C.C60，B45，AB

43.如图，已知12，ACAD，增加下列条件：①ABAE；②BCED；③CD；④BE。其中能使ABCAED的条件有()

A.4个B.3个C.2个D.1个

4.如图，12，CD，AC,BD交于E点，下列不正确的是()

A.DAECBEB.CEDE D.EAB是等腰三角形 C.DEA不全等于CBE

乐学堡辅导中心内部资料注意保存

5.如图，已知ABCD，BCAD，B23，则D等于()

A.67 C.23B.46D.无法确定

二、填空题：

6.如图，在ABC中，C90，ABC的平分线BD交AC于点D，且

CD:AD2:3，AC10cm，则点D到AB的距离等于__________cm；

7.如图，已知ABDC，ADBC，E,F是BD上的两点，且BEDF，若

AEB100，ADB30，则BCF____________；

8.将一张正方形纸片按如图的方式折叠，BC,BD为折痕，则CBD的大小为_________；

9.如图，在等腰RtABC中，C90，ACBC，AD平分BAC交BC于D，

DEAB于E，若AB10，则BDE的周长等于____________；

10.如图，点D,E,F,B在同一条直线上，AB//CD，AE//CF，且AECF，若

BD10，BF2，则EF___________；

三、解答题：

11.如图，在ABC中，ABBC，ABC90。F为AB延长线上一点，点E在BC上，BEBF，连接AE,EF和CF。求证：AECF。

12.如图，D是ABC的边BC上的点，且CDAB，ADBBAD，AE是ABD的中线。求证：AC2AE。

13.如图，在ABC中，ABAC，12，P为AD上任意一点。求证：ABACPBPC。

ABC为等边三角形，14.如图，点M,N分别在BC,AC上，且BMCN，AM与BN

交于Q点。求AQN的度数。

15.如图，ACB90，ACBC，D为AB上一点，AECD，BFCD，交CD

2教案全等三角形教师版篇6

教学设计

23.3 相似三角形

23.3.2 相似三角形的判定（1）

教学目标：

1．会说出识别两个三角形相似的方法，有两个角分别相等的两个三角形相似.2．会用这种方法判断两个三角形是否相似.教学过程：

一、复习

1．两个矩形一定会相似吗?为什么? 2．如何判断两个三角形是否相似? 根据定义：对应角相等，对应边成比例.3．如图△ABC与△A′B′C′会相似吗?为什么?是否存在识别两个三角形相似的简便方法?本节就是探索这方面的识别两个三角形相似的方法.二、新课讲解

同学们观察你与你的同伴所用的三角尺，以及老师用的三角板，如有一个角是30°的直角三角尺，它们的大小不一样.这些三角形是相似的，我们就从平常所用的三角尺入手探索.(1)是45°角的三角尺，是等腰直角三角形会相似.(2)是30°的三角尺，那么另一个锐角为60°，有一个直角，因此它们的三个角都相等，同学们量一量它们的对应边，是否成比例呢? 这样，从直观上看，一个三角形的三个角分别与另一个三角形三个角对应相等，它们好像就会“相似”.是这样吗?请同学们动手试一试：

1．画两个三角形，使它们的三个角分别相等.画△ABC与△DEF，使∠A＝∠D，∠B＝∠E，∠C＝∠F，在实际画图过程中，同学们画几个角相等?为什么? 实际画图中，只画∠A＝∠D，∠B＝∠E，则第三个角∠C与∠F一定会相等，这是根据三角形内角和为180°所确定的.教学资料

应有尽有

百度文库

教学设计

2．用刻度尺量一量各边长，它们的对应边是否会成比例?与同伴交流，是否有相同结果.3．发现什么现象：发现如果一个三角形的三个角与另一个三角形的三个角对应相等，那么这两个三角形相似.4．两个矩形的四个角也都分别相等，它们为什么不会相似呢?

这是由于三角形具有它特殊的性质.三角形有稳定性，而四边形有不稳定性.于是我们得到识别两个三角形相似的一个较为简便的方法：

如果一个三角形的两角分别与另一个三角形的两角对应相等，那么这两个三角形相似，简单地说：两角对应相等，两三角形相似.同学们思考，能否再简便一些，仅有一对角对应相等的两个三角形，是否一定会相似呢? 例题：

1．如图，两个直角三角形△ABC和△A′B′C′中，∠C＝∠C′＝90°，∠A＝∠A′，判断这两个三角形是否相似.2．在△ABC与△A′B′C′中,∠A＝∠A′＝50°，∠B＝70°，∠B′＝60°，这两个三角形相似吗? 3．如图，△ABC中，DE∥BC，EF∥AB，试说明△ADE∽△EFC.三、练习

1．△ABC中，∠ACB＝90°，CD⊥AB于D，找出图中所有的相似三角形.2．△ABC中，D是AB的边上一点，过点D作一直线与AC相交于E，要使△ADE与△ABC会相似，你怎样画这条直线，并说明理由.和你的同伴交流作法是否一样?

教学资料

应有尽有

百度文库

教学设计

四、小结

本节课我们学习了识别两个三角形相似的简便方法：有两个角对应相等的两个三角形相似.五、作业 P67练习1，2

教学资料

2教案全等三角形教师版篇7

TEACHING AIMS:

1. Learn and master the useful words and expressions in the period.

2. Train the students’ reading ability.

3. Help the students to know more about world records.

TEACHING IMPORTANT POINTS:

1. Master the following phrases and sentence pattern:

valuate, various, key, origin, equip, puzzle, wealthy, Asian, African, ambassador, wander, motherland, existence, navy, treasure, command, royal, embassy, zebra, volunteer, radium, dam, suggest, accomplish, sickness, unable, sacred, refer, aircraft, arise, evidence, chairman, praise, in the name of, in exchange for, set sail, in return, bring up, apart from, refer to, run out

2. Improve the students’ reading ability.

TEACHING DIFFICULT POINTS:

1. How to help the students understand the passage better. And how to help the students understand the sentence pattern and use it freely

2. It is well known that Africa had contacts with India and the Red Sea civilizations form the earliest times.

3. It was a major development that the Africans were reaching out to China.

4. The wonderful gift and the contact with the black court so excited China’s curiosity about Africa that Zheng He sent a message to the king and to other African states, inviting them to send ambassadors and open embassies in the new Ming capital, Beijing.

5. The exchange of goods had a symbolic meaning far more important than the value of the goods themselves.

6. All that was left to be conquered was the “third pole”, the highest mountain on earth, Mount Qomolangma, some suggested that it not be accomplished.

7. Climbing at such high altitudes requires great skill and is not without risk.

8. Apart from the cold, thin air and low oxygen levels can cause mountain sickness, which can kill.

教学随笔

______________________________

_____________________________

9. They had no idea what they were up against and failed to reach the top.

10. The local Tibetans and Sherpas laughed at the strange bottles containing what they referred to as “English air”.

11. In later years the question arose who was the first in the team to reach the top.

12. When their oxygen ran out, they had no chance of surviving.

13. The New Zealander Edmund Hillary and the Sherpa Tenzing Norgay, as members of a British team, were the first to make it to the summit of Mount Qomolangma.

14. Tasman sailed past Australia without seeing the continent, but discovered Tasmania and the west coast of New Zealand, which he thought was part of the southern continent.

15. What he needed was a new pair of glasses because what he had seen were not people but penguins.

16. He was positive about the existence of a large unknown continent, and believed its northern coast to be lying somewhere in the Pacific Ocean.

17. Unable to find it, he decided to set sail for New Zealand, which had already been discovered by the Dutch.

Period 1. Word Study.

1. evaluate vt, evaluation c.n. 评价;估计

eg. The school has only been open for six months, so it’s hard to evaluate its success.

该学校刚开办了六个月，现在还很难估计它的成就。

2. various adj, variety n, a variety of, 各种各样的

3. in the name of 以…的名义, name sb./sth. after 以…的名字命名

eg. Animal experiments are carried on in the name of science.

一些残酷的动物实验是以科学的名义进行的。

4. equip v. (equipped, equipped) 配备; 装备

equipment u.n. 设备，装备

equip sb./ sth. with sth. = supply sb./ sth. with 用…装备

equip sb. for使某人有能力胜任

sb. be equipped to do sth. 使某人有做准备做某事

eg. We’ll have to equip our office with word processors, won’t we?

我们公司应该备有文字处理机，不是吗?

教学随笔

______________________________

We were just not equipped to deal with the problem.

我们没准备好，根本应付不了这个问题。

5. puzzle c.n. & vt.

c.n. 难题;迷

vt. 使困惑;使糊涂 puzzle sb

puzzled 感到困惑的 be puzzled about 对…感到困惑的

puzzling 令人感到困惑的

6. wealthy adj. 富有的，有财产的

wealth u.n. 富有，财产 her great wealth 她的巨额财产

a wealth of +u.n./c.n. 大量;丰富, a wealth of examples 大量事例

7. wander vi. & vt. 徘徊;流浪，广义用语，有信步而行之意

Beautiful deer wander all over this island.岛上有美丽的鹿儿游荡。

loiter 徘徊;闲荡;有逗留或徘徊不去之意

ramble 漫步，逍遥;指在海岸或林中等，有闲适之意

I ramble through the village.

我漫步穿过村庄

roam 徘徊;漂泊;指在陆海路较远的距离徘徊，不安定

My eyes roam over the sea and island.

我带着不安眺望大海和岛屿。

rove 漫游;漂泊;无一定目的，且范围较广

No lady would rove about the heath.

无一女士愿漫游此荒凉之地。

stroll 逍遥;散步;指在大街或园中悠闲而徐缓地信足散步。

He strolled out into the garden.

他信步出去进入花园。

range 徘徊;通常指具有目的的在较大的范围内徘徊，如在森林中寻找猎物等。

The wild beast ranges the forest in search of prey.

那野兽在森林中徘徊，寻找猎物。

8.accurate adj. 正确无误的;准确的

inaccurate adj. 不准确的

accuracy u.n. 准确性;精确性

eg. Is that station clock accurate?

9. arise vi. (arose, arisen) 出现，呈现，发生

arise from/out of 由…引起产生

eg. Some unexpected difficulties/opportunities have arisen. 出现了一些意外的困难。

A storm arose during the night. 夜间起风暴了。

教学随笔

______________________________

_____________________________

10. royal adj. 王室的，皇家的

royalty n. 皇室成员

royalistic adj. 保皇党派的

royalism n. 君主主义

royalist n. 保皇主义者

11. bring up 培养，提出呕出

bring about 带来，造成 bring about great changes 带来巨大变化

bring down 使倒下，使下降 bring down the price 降价

bring in 提出，引进，增加

bring on 引起，导致，有助于

bring out 使显现，阐明，出版

13. refer to

1) 参考，查阅 refer to the text 参照课文

2) 提及 Don’t refer to the matter again. 别再提这件事了。

3) 指…而言，指的是

When I said some people are stupid I wasn’t referring to you.

当我说有些人很笨的时候，我不是指你。

4) 适用于 This rule refers to everyone. 这条规则适用于任何人。

5) 把…称作 refer to sb./sth. as …

6) refer…to = owe …to 归功于

14. run out of = use up vt. 用完

run out vi.

eg. I have run out of /used up ink. = My ink is running out.

Period 2 Warming up, listening and speaking.

1. evaluate 评价，估计，估量，

1) It’s hard to __A__ her as a singer.

A. evaluate B. reduce C. achieve D. fade

2) It’s impossible to __B__ these results without knowing more about the research methods employed.

A. value B. evaluate C. absorb D. benefit

2. various vary, a great variety of,

1) 多方面的经验 various experience

2) He can’t complete his paper on time for __B__ reasons, which are true.

A. different B. various C. sort of D. kinds

教学随笔

______________________________

_____________________________

3) A great variety of flowers __A__ on show in the street on National Day.

A. were B. was C. appeared D. had

3. take possession of 占领，占有，夺取，没收，

1) The policeman took possession of the thief’s bag. 没收

2) The soldiers took possession of the enemy’s fort. 夺取

3) have possession of 占领，拥有

4) be in (the) possession of 占领，拥有，(被…拥有)

5) be in one’s possession 在某人手中，由…掌握，

6) Almost everything __D___ the enemy after the war.

A. took possession of by B. took possession of

C. was taken possession by D. was taken possession of by

7) The house is __C__ Mr Wang.

A. taking possession of B. in possession of

C. in the possession of D. taking the possession of

4. in the name of 以…的名义，代表，凭借…的权威，

1) I arrest you in the name of the law. 以法律的名义

2) Let me thank you in the name of us all. 代表我们大家

3) a war waged in the name of liberation 借解放的名义

4) by name 用名字(叫) 5) by the name of 名收做…

6) call one names 骂人 7) under the name (of)以…为(笔)名

8) Have you ever heard of the pop group __B__ itself “Black Birds”?

A. called B. calling C. to call D. call

9) In old movies, the police shouted “Open up __A__ the law” before they broke the door down.

A. in the name of B. at the mercy of

C. by the name of D. regardless of

5. origin 起点，来源，出身，original,

1) the origin of civilization / human race …的起源

2) a man of noble / humble origin(s) 出身高贵/卑贱之人

3) Some Japanese words are of Chinese origin.

= Some Japanese words are Chinese 起源于中文

4) Her mother is French by origin. 原籍法国

教学随笔

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6. equip equipment, equip…with…, be equipped with,

1) All cars nowadays are __D__ with safety belts.

A. prepared B. packed C. built in D. equipped

2) The boys __B__ themselves with food, tents and sleeping bags for their journey.

A. prepared for B. equipped C. afforded D. equaled

Period 3 Reading 1

1. Scanning the text to learn something about world records.

2. Fast and careful reading to get the detailed information in the text.

3. Individual, pair or group work to make every student work in class.

Step1 Scanning

Judge the following sentences True or False

1. The Europeans were the first Explorers to travel to other countries.

2. Accurate maps of the countries around the Indian Ocean were made before the fifteenth century.

3. In the years between 1405 and 1433, Zheng He sailed westwards only on voyages of exploration.

4. Zheng He invited African countries to send ambassadors to China.

Step 2

Read the passage and point out the topic sentence for each paragraph.

Para. 1 thesis sentence(论题) Many great explorers made expeditions across the Indian Ocean long before Columbus, among whom Zheng He was the most outstanding.

Para. 2 China had contacts with countries along the Indian Ocean from the early times, and during ancient time explorers had begun to contact with each other.

Para 3. Between the Han and the early Tang Dynasty, Swahili kingdom and the islands off the African coast developed into the world trade center and attracted merchants from the world.

教学随笔

be equipped to do sth,

supply sb with sth,

supply sth to sb,

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(F) Brave merchant

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(F) no accurate maps

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(F) and trade

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(T)

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Para. 4. During the Tang Dynasty, Du Huan, who traveled to many lands, wrote the book Record of My Travels.

Para. 5 In the 11th century the Africans made several voyages to the court of the Song Dynasty.

Para 6. By the beginning of the 15th century the time was ripe for a grand meeting.

Para 7. In the years between 1406 and 1433, under the command of Zheng He, seven large treasure fleets sailed westwards on voyages of trade and exploration.

Para 8. Zheng He renewed relations with the kingdom of the East African coast.

Para 9. The fleet made several expeditions before the exploration was stopped.

Multiple choice:

1. Who were (was) the earliest explorer(s) of the Western Ocean? __D__

A. Marco Polo B. Christopher Columbus

C. European explorers D. Brave merchants

2. Through the Silk Road, China got __A__ from other countries.

A. spices and glass B. silk C. weapons D. milk

3. An African king gave rhinoceros horns to China in order to __C___.

A. make money B. stop the war

C. show his friendship D. award the Ambassador

4. Which of the following became the world’s trading center over a few centuries after Han Dynasty? __C__

A. Ceylon. B. India.

C. Swanhili kingdoms. D. Egypt.

5. In Du Huan’s book “Record of My Travels” you can learn about __B__.

A. Marco Polo B. many foreign countries

C. Christopher Columbus D. ways to make silk

6. Who does “The Chinese Columbus” refer to?

A. The Ming emperor. B. Du Huan.

C. The Chinese ambassador. D. Zheng He.

教学随笔

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7. The text is mainly about __D__.

A. how the Silk Road was formed

B. how China developed trading relations with Arabic countries

C. Zheng He’s expeditions across the Indian Ocean

D. the history of China’s opening to the outside world

8. The small bronze statue of a lion found in Shanga most probably came from __A__.

A. China B. Rome C. Greece D. London

9. “In the east, China prospered under a new dynasty.” The underlined part refers to __D__.

A. the Han Dynasty B. the Song Dynasty

C. the Qin Dynasty D. the Ming Dynasty

10. Which of the following can be inferred from the text?

A. Columbus’ exploration was stopped for economic reasons. __D__

B. No accurate maps of the countries around the Indian Ocean existed before Zheng He.

C. In the Ming Dynasty China had the most powerful navy in the world.

D. The giraffe was an animal that could not be found in China in the Ming Dynasty.

Step 3

Put the sentences in good order.

1. In the eleventh century, the Africans made several voyages to the court of the song dynasty.

2. Merchants from the Arabic countries began to travel to the Swahili kingdom and the islands off the African coast to trade with them.

3. People of the Han Dynasty exchanged silk for spices and glass with Indians and Romans by way of the Silk Road.

4. The Chinese traveller, Du Huan, wandered through Arabic countries for about 10 years.

5. Christopher Columbus and other European explorers searched for routes to Asia.

6. Zheng He made seven voyages and discovered the eastern coast of Africa.

Order: 3 2 4 1 6 5

教学随笔

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Period 4 Reading 2

1. Trade and curiosity have often formed the foundation for mankind’s greatest endeavor. 贸易和好奇常构成人类最大努力的基础.

1) He endeavored to win votes for his proposal.

endeavor to do sth 比 try to do sth 语气更强

2. puzzle puzzlement, puzzling, puzzled,

1) No one has yet succeeded in explaining the puzzle of how life began. 成功诠释人类起源之迷

2) The murder case was a puzzle to the detective. 难题

3) That’s what puzzles me. v 使困惑

4) I’m puzzled (about) what to do next. 不知道，have no idea.

5) The situation was more puzzling than ever. 使人困惑的

6) 字迷 a word puzzle 文字游戏 a crossword puzzle

7) Facing the __A__ situation the sales manager looked ______.

A. puzzling, puzzled B. puzzling, puzzling

C. puzzled, puzzled D. puzzled, puzzling

8) On his face there was a __D__ expression which we couldn’t understand.

A. puzzle B. puzzles C. puzzling D. puzzled

3. However, long before that brave merchants were the real explorers of the Western Ocean. 然而, 在那之前很久, 勇敢的商人是真正的西洋探险者.

1) He’ll be back before long. soon

2) It won’t be long before you get well. 不久…就…

3) I had learned some English long before I came here. ____

4. in exchange for exchange sth for sth

1) I gave her a sweater __A__ a skirt.

A. in exchange for B. in exchange of

C. in return for D. in return of

2) I’d like to do something for you __C__ everything you’ve done for me.

A. in exchange B. in turn

C. in return for D. in terms of

教学随笔

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lay the solid foundation of science fiction

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比较：不久…就… / 过…多久才…

It wasn’t long before the war broke out.

It was two years before I saw her.

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conj 在我来这儿好久前

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5. In 97 AD, Gan Ying, a Chinese ambassador, went to the East Roman Empire over land and returned to Luoyang with a present from an African king – rhinoceros horns. 公元97年, 汉朝大使甘英由陆路到达东罗马为帝国, 返回时带着一件非洲国王馈赠的礼物 – 犀牛角.

1) The water was over my knees. 淹没

2) She spread a clean cloth over the table. 铺在…上面

3) The horse jumped over the fence. 越过

4) I think he is well over fifty. 五十开外

5) I traveled (all) over Scotland this summer. 游遍

6) She has been ill in bed over the past week. 整个星期

7) They argued over money matters. 为…事

8) I heard the news over the radio. 从(广播，电视)

6. develop in to the world’s trading center 发展成了世界贸易中心 development, developed, developing

1) He believes that sports can develop mind and body. ____

2) He developed the little store into a big department store.

3) Land animals are thought to have developed from sea animals. 由…进化而来

4) She has developed into a beautiful woman. ________

7. The Arabic contacts to the African coast led to the next meeting between black people and a Chinese. 阿拉伯(国家)与非洲沿海的接触导致后来黑人与一位华人的会面.

1) The discovery of evidence led to __C__.

A. the thief having caught B. catch the thief

C. the thief being caught D. the thief to be caught

2) It is sleeping late in the morning that _D_ late for work.

A. devotes to being B. is led to being

C. leads to be D. leads to being

3) – Have you been in __B__ with Andrew recently?

-- Only by telephone.

A. communication B. contact C. connection D. link

8. wander 漫游，游荡，流浪

1) He was wandering about in the forest. 在森林中徘徊

2) I spent the vacation wandering through France. 漫游

3) He wandered off the subject. 他说得离了题。

教学随笔

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over/during/in the past … 用于完成时

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有益于身心发展

把…发展成为，be developed into

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她出落得亭亭玉立。

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wonder, wonderful,

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9. It was a major development that the Africans were reaching out to China. 非洲向中国的延伸是一大进步。

1) Let’s keep to the point or we __A__ any decisions.

A. will never reach B. have never reached

C. never reach D. never reached

2) I keep the medicines on the top shelf, out of the children’s __B__.

A. reach B. hand C. hold D. place

10. date from date back to, 只用主动态及一般现在时

1) My interest in maths __A__ the time I met a good maths teacher in junior middle school.

A. dates from B. keeps from

C. is dated back to D. goes back to

2) These old buildings possibly __B__ the Ming Period.

A. are dated back to B. date from

C. are dated from D. date

11. existence exist, there exist(s), 区别：exit,

1) When did this world come into existence? 产生

2) Do you believe in the existence of ghosts? 相信鬼的存在

3) We can’t exist without food and water. 生存，live

12. no accurate maps of the countries around the Indian Ocean existed 没有环印度洋国家的标准地图 ________

1) 事件的正确报道 ______________________________

2) 正确地说 ____________________________________

3) He is accurate in his judgment (at figures). __________

13. In the east, China prospered under a new dynasty. 在东方，中国处于一个新朝代的繁荣时期。

1) 他的生意兴隆。 His business prospered.

2) 我听说他的儿子很有成就。

I hear his son is prospering.

3) When we are in England, China is an __D__ country.

A. east B. Easter C. eastward D. eastern

4) America faces the Atlantic __D__.

A. from the east B. in the east

C. to the east D. on the east

14. under the command of Zhen He, …

1) 在…的统治下 under the rule of

教学随笔

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reach/achieve one’s goal

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within one’s reach

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但：the building dating back to …

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come into being

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prosperous, prosperity,

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2) 在…的领导下 under the leadership of

3) Nobody obeyed the teacher’s command to stop chatting.

4) The policeman commanded him to stop. 命令，order

5) The teacher commanded that he (should) go out. ______

15. set sail (to/from/for/…) _________________________

1) The scientific research team set sail for the South Pole.

2) It was four weeks’ sail from Shanghai to Japan in the past.

3) It’s only two hours’ ride from Datong to Beijing. ______

16. royal royalty, be loyal to

1) 王宫 a royal palace 2) 王室 a royal family

3) 王权 royal power 4) 英国皇家海军 the royal navy

5) 王冠 royal crown 6) 捷径 royal road, short cut

17. volunteer ___________________________________

1) The young man volunteered to stop the drunken men from fighting. 自告奋勇

2) I volunteered for his election campaign. __________

18. bring up 把…扶养成人，带来，呕吐，

1) Lily __D__ in a big city, while her twin sister Lucy was ______ in a small village by her grandmother.

A. grew up, grown up B. brought up, grown up

C. was grown up, brought up D. grew up, brought up

2) After Xiao Li arrived in London, she found it was far more difficult to __B__ living on her own.

A. rely on B. adjust to C. bring up D. look into

Period 5 Integrating Skills

1. suggest make a suggestion, a suggested answer,

1) The latest figures put forward by the state suggested that the business __A__ improving.

A. was B. be C. being D. should

2) Jane’s pale face suggested that she __B__ ill, and her parents suggested that she ______ a medical examination.

A. be, should have B. was, have

C. should be, had D. was, has

教学随笔

听从，服从，

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虚拟语气：should + 动词原形

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驶向(目的地) for: 具体目的地，

to: 方向或目的地，

from: 起点

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志愿为他的选举助一臂之力

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suggest sth to sb,

suggest doing,

suggest (to sb) that … (should) …

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3) He came to my class every week, but his attitude __D__ he was not really interested in the subject.

A. expressed B. described C. explained D. suggested

2. accomplish 成功地完成预期目标，任务，

finish 完成日常事务，了结，

achieve 排除困难完成宏伟计划或大业，

complete 完整地完成，终结，用法较正式，

1) We tried to settle the argument but accomplished nothing.

2) I finished reading the book yesterday.

3) By hard working we can achieved anything.

4) I need one more stamp before my collection is completed.

3. apart from …(别无)，除…外(尚有)，besides, except,

1) Good work, apart from a few slight faults. ________

2) Apart from being too large, the hat doesn’t suit me. ____

3) __D__ them, I had no one to talk to.

A. Take apart B. Set apart C. Fall apart D. Apart from

4) __D__ you and me, I don’t think there was anyone there under thirty.

A. Including B. Beside C. In addition D. Apart from

4. They had no idea what they were up against. 他们不知道他们面对的(困难)什么。

1) 他们面临大麻烦。They are up against a great trouble.

5. refer to _______________________________________

1) I don’t know who she was referring to when she said that.

2) There’re certain people to whom this order does not refer.

3) In the course of his speech, he referred several times to his notes. ________

4) He often referred to his past experiences as a peasant.

5) The Local Court decided to refer the case to the High Court. ________

6) He referred his success to the good education he had had.

7) When I said that some students were so lazy that they couldn’t hand in their exercise books, I __C__ to you.

A. didn’t refer B. hasn’t referred

C. wasn’t referring D. don’t refer

教学随笔

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除一些小毛病外，活儿(工作)挺好的。

除太大外，这顶帽子也不适合我。

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指…, 意思是指…,

适用于…,

看，参阅，

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提起过去当农民的经历，

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移交，

归结于，归功于，

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8) – Please don’t take the books out of the reading room.

-- No, I won’t. I just want to _B_ them for some figures.

A. mention B. refer to C. look at D. look into

6. run out (of) run out vi, run out of, vt,

1) We are fast running out of cigarettes. ________

2) Can you give me a cigarette? Mine have run out. ______

7. arise vi, arose, arisen, 产生，出现，happen, appear,

rise vi, rose, risen, 升起，上涨，

raise vt, raised, raised, 举起，增加，筹集，…,

1) New difficulties will arise from such situation.

2) A problem has arisen with the new computer.

3) The curtain rose and the play began.

4) They raised the curtain and the play began.

5) The soldiers __D__ the flag every morning outside the barracks.

A. rise B. arouse C. arise D. raise

6) Her temperature is still __B__.

A. raising B. rising C. risen D. arising

7) Should the opportunity __C__, I’d love to go to Paris.

A. rise B. raise C. arise D. happen

8. praise prize, the Nobel Prize for physics

1) 热烈颂扬，唱赞歌 sing one’s/sb’s (own) praise

2) 把某人捧上了天 praise sb (up) to the skies,

3) 赞扬一个人的英勇 praise a man for his courage

4) Our guests praised the meal as the best they had had for years. 称赞…是…,

9. sacred 注意区分：secret,

1) 神圣的建筑物 a sacred building, 教堂，寺院，神殿，

2) 圣典 a sacred book 3) 宗教音乐 sacred music

4) 郑重的诺言 a sacred music

5) 林肯纪念碑 a monument sacred to the memory of Lincoln

教学随笔

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我们的香烟很快就用完了。

抽完。

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sing the praise of sb,

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Unit 2 同步练习

一. 单项填空

1. He often think of he can do for his country.

A. what B. how C. that D. which

2. the cost, the hat doesn’t suit me.

A. Apart from B. Including

C. Without D. Together with

3. My money . I must go to the bank to draw some of my savings out before I’ve none in hand.

A. has run out B. is running out

C. has been run out D. is being run out

4. Finding a job in such a big company has always been his widest dreams.

A. under B. over C. above D. beyond

5. According to the weather forecast, which is usually , it will snow this afternoon.

A. accurate B. precise C. exact D. perfect

6. Many difficulties have as a result of the change over to a new type of fuel.

A. risen B. arisen C. raised D. arrived

7. - I want to buy a present for my friend’s birthday, but I’m not sure what to buy.

-Well, I think I can help you make a .

A. suggestion B. speech C. decision D. promise

8. The latest data put forward by the states suggested that the business improving.

A. was B. be C. being D. should

9. The best method to this goal is to unite as many sympathetic people as possible with the labor movement itself.

A. win B. accomplish C. finish D. complete

10. I shall have a companion in the house after all these years.

A. single B. only C. alone D. lonely

11. good, the food was soon sold out.

A. Tasted B. Being tasted

C. Tasting D. Having tasted

教学随笔

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12. is no doubt that he will pass the exam.

A. There B. It C. This D. That

13. was known to all, William had broken his promise he would give us a rise.

A. As; which B. As; that

C. It; that D. It; which

14. It was about 600 years ago the first clock with a face and an hour was made.

A. that B. until C. before D. when

15. If you tomorrow, I treat you a big dinner.

A. are going to come; will B. were going to come; would

C. were to come; would D. will; would

16. In old movies, the police shouted “Open up ______ the law” before they broke the door down.

A. in the name of B. at the mercy of

C. by the name of D. regardless of

17. I warned them not to do it, but my objections were ______.

A. set sail B. set about C. set aside D. set down

18. Captain Cook commanded his men _____ into the sea.

A. jump B. jumped C. had jumped D. would jump

二.单词填空

1.As they lacked experience of how to teach the disabled children, the problems a_________ one after another.

2.What p________ the villagers most was that the footmarks in the snow were much larger than a human being’s.

3.Up to now , there has been no e________ to prove that he has sth to do with the theft.

4. Before the final exam, the teacher told all the students to e_____________ themselves with sharp pencils, pens, rules, and rubbers.

5. A___________ (各种各样的)of out-of-class activities are organized in that school for the purpose of building up students’ characters and forming their collective senses.

6. The Tongbai Mountain area is the ____________(源头)of the Huai River.

教学随笔

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_____________________________

7. Anyway, your ____________(估计)of his potential turned out to be a failure.Now,he has become one of the best on our basketball team.

8. He quarreled with his wife and left his home. He did nothing but ____________(游荡)in the street.

9. He says that he will work as a _____________(志愿者) when the 29th Olympic Games are held in Beijing.

三.阅读理解

Lions are opportunists. They prefer to eat without having to do too much work. When resting in the shade, they are also watching the sky to see what is flying by, and even in the heat of the day they will suddenly start up and run a mile across the plains to find out what is going on. If another animal has made a kill, they will drive it off and take the dill for themselves. A grown lion can easily eat 60 pounds of meat at a single feeding. Often they eat until it seems painful for them to lie down.

The lionesses (母狮) , being thinner and faster, are better hunters (猎手) than the males (雄狮). But the males don’t mind. After the kill they move in and take the test share.

Most kills are made at night or just before daybreak. We have seen many, many daylight attempts but only ten kills. Roughly, It’s about twenty daytime attempts for one kill.

When lions are hiding for an attack by a water hole, they wait patiently and can charge at any second. The kill is the exciting moment in the day-to-day life of the lion, since these great animals spend most of their time, about 20 hours a day, sleeping and resting.

Lions are social cats, and when they are having a rest, they love to touch each other. After drinking at a water hole, a lioness rests her head on another’s back. When walking, young lions often touch faces with older ones, an act of close ties among members of the group.

64. By describing lions as “opportunists” in the first paragraph, the author means to say that lions .

教学随笔

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A. are cruel animals B. are clever animals

C. like to take advantage of other animals

D. like to take every chance to eat

65. According to the text, which of the following is true?

A. Lions make most kills in the daytime.

B. Males care more about eating than active killing.

C. Lions are curious about things happening around them.

D. It doesn’t take lions too much time to make a kill.

66. How can we know that lions are social animals?

A. They depend on each other.

B. They look after each other well.

C. They readily share what they have.

D. They enjoy each other’s company.

67. What would be the best tiltle for the text?

A. Powerful Lions B. Lions at Work and Play

C. Lions, Social Cats D. Lions, Skilled Hunters

To extinguish (熄灭) different kinds of fires, several types of fire extinguishers have been invented. They must be ready for immediate use when fire breaks out. Most portable (手提式的) kinds operate for less than a minute, so they are useful only on small fires. The law requires ships, trains, buses and planes to carry extinguishers.

Since fuel, oxygen (氧气) and heat must be present in order for fire to exist, one or more of these things must be removed or reduced to extinguish a fire. If the heat is reduced by cooling the material below a certain temperature, the fire goes out. The cooling method is the most common way to put out a fire. Water is the best cooling material because it is low in cost and easy to get.

Another method of extinguishing fire is by cutting off the oxygen. This is usually done by covering the fire with sand, steam or some other things. A blanket may be used do cover a small fire.

A third method is called separation, which includes removing the fuel, or material easy to burn, from a fire, so that it can find no fuel.

The method that is used to put out a fire depends upon

教学随笔

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the type of fire. Fires have been grouped in three classes. Fires in wood, paper, cloth and the like are called Class A fires. These materials usually help keep the fire on. Such fires can be stopped most readily by cooling with water.

68. If a fire breaks out on a bus, which of the follow should be ready there for you to use?

A. Sand B. Water C. A blanket. D. An extinguisher.

69. To cover a small piece of burning wood with a basin in order to stop the fire is an example of .

A. separating the fire B. reducing the heat

C. removing the fuel D. cutting off the oxygen

70. In choosing how to put out a fire, we should first be clear about .

A. when it breaks out B. how it comes about

C. what kind it is D. where it takes place

71. What would the author probably discuss in the paragraph that follows?

A. Another class of fires B. Another type of extinguishers

C. How fires break out. D. How fires can be prevented.

Childhood was an illusion (错觉) and the illusion was this: everything was bigger. No, I mean everything, not just houses and shops and grown-ups, but colors and flowers and journeys, especially journeys which seemed endless. “Are we there yet, Daddy?”

Funfairs (游乐场) were huge things that spread for miles around you with noise and lights and exciting danger. Rainy days at home when you were ill seemed to last for ever. Being a grown-up yourself was an unthinkable distant possibility. Every sound was louder, every game was grander, every pain unbearable.

As I’ve grown old, life has become smaller. Tastes have bulled. Surprises have lured into shocks. Days go by unnoticed. How can I regain childhood when it was an illusion?

I have only one repeatable and wonderful way and even in this way I can regain only part of that larger world. I can play upon the stage like a child and make the crowd laugh

教学随笔

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and laugh with them, sometimes helplessly like a child, and then, even though I’m a sixty-one-year-old man, I can almost catch the colors and sounds and stillness of those bigger years when I was little.

72. How does the author feel about his childhood?

A. It was endless. B. It was unpleasant.

C. He is glad that it is over. D. He misses it as a grown-up

73. The author thinks that everything was bigger in childhood because .

A. children could not make proper judgments.

B. children were curious and eager about life

C. things appeared really big in children’s eyes

D. to grow up seemed so long for children

74. The world seems to have become smaller to the author because .

A. life is disappointing B. time goes by too fast

C. he has had too many surprises

D. foods no longer taste delicious

75. The author enjoys playing on the stage so as to .

A. act like a child B. live an unusual life

C. make the crowd laugh D. regain his childhood

四.书面表达

假设你是李华，作为选派的交流学生在美国某中学学习了一年，寄住在Mr. Brown家里，刚回到国内。回国后你发现自己的一本英语词典遗忘在他家，因此给他写一封信，请他帮助寄回词典。信的主要内容如下：

1. 感谢在美国期间他所提供的帮助。

2. 一本英语词典忘记带回。

3. 词典是美国老师送的，非常珍贵。

4. 词典很可能丢在卧室的书架上。

5. 邮资自己付。

注意：

1. 词数100左右;信的开头和结尾已为你写好。

2. 可适当增加细节，以使行文连贯。

3. 参考词汇：邮资: postage

U2同步练习参考答案

一、单项选择

1-5. AABDA 6-10. BCBBD

11-15. CABAC 16-18 CCA

二、单词拼写

arose/appeared, puzzled,

evidence, equip, variety,

origin, evaluation, wander,

volunteer

三、阅读理解

64~75 CBDBDDCADBAD，

四、书面表达

One possible version ：

Dear Mr. Brown,

I’m now safely back home. Thank you very much for all the kindness I got from you during my stay. Hope everything is fine with you there.

Now I wonder whether I could ask you a favor. When I came back, I suddenly realized that I had left my English dictionary behind at your place. It is a precious gift from my American teacher. Would you please be so kind as to send it back to me? I’ll pay for the postage. The dictionary must be on the bookshelf in my bedroom. It is the one with a red cover.

Thanks and all the best.

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