跟踪训练1在正方体ABCD-A1B1C1D1中,E为AC的中点.求证:(1)BD1⊥AC;(2)BD1⊥EB1.(2)∵(BD_1 ) ?=(-1,-1,1),(EB_1 ) ?=(1/2 "," 1/2 "," 1),∴(BD_1 ) ?·(EB_1 ) ?=(-1)×1/2+(-1)×1/2+1×1=0,∴(BD_1 ) ?⊥(EB_1 ) ?,∴BD1⊥EB1.证明:以D为原点,DA,DC,DD1所在直线分别为x轴、y轴、z轴,建立如图所示的空间直角坐标系.设正方体的棱长为1,则B(1,1,0),D1(0,0,1),A(1,0,0),C(0,1,0),E(1/2 "," 1/2 "," 0),B1(1,1,1).(1)∵(BD_1 ) ?=(-1,-1,1),(AC) ?=(-1,1,0),∴(BD_1 ) ?·(AC) ?=(-1)×(-1)+(-1)×1+1×0=0.∴(BD_1 ) ?⊥(AC) ?,∴BD1⊥AC.例2在棱长为1的正方体ABCD-A1B1C1D1中,E,F,M分别为棱AB,BC,B1B的中点.求证:D1M⊥平面EFB1.思路分析一种思路是不建系,利用基向量法证明(D_1 M) ?与平面EFB1内的两个不共线向量都垂直,从而根据线面垂直的判定定理证得结论;另一种思路是建立空间直角坐标系,通过坐标运算证明(D_1 M) ?与平面EFB1内的两个不共线向量都垂直;还可以在建系的前提下,求得平面EFB1的法向量,然后说明(D_1 M) ?与法向量共线,从而证得结论.证明:(方法1)因为E,F,M分别为棱AB,BC,B1B的中点,所以(D_1 M) ?=(D_1 B_1 ) ?+(B_1 M) ?=(DA) ?+(DC) ?+1/2 (B_1 B) ?,而(B_1 E) ?=(B_1 B) ?+(BE) ?=(B_1 B) ?-1/2 (DC) ?,于是(D_1 M) ?·(B_1 E) ?=((DA) ?+(DC) ?+1/2 (B_1 B) ?)·((B_1 B) ?-1/2 (DC) ?)=0-0+0-1/2+1/2-1/4×0=0,因此(D_1 M) ?⊥(B_1 E) ?.同理(D_1 M) ?⊥(B_1 F) ?,又因为(B_1 E) ?,(B_1 F) ?不共线,因此D1M⊥平面EFB1.
问题导学类比椭圆几何性质的研究,你认为应该研究双曲线x^2/a^2 -y^2/b^2 =1 (a>0,b>0),的哪些几何性质,如何研究这些性质1、范围利用双曲线的方程求出它的范围,由方程x^2/a^2 -y^2/b^2 =1可得x^2/a^2 =1+y^2/b^2 ≥1 于是,双曲线上点的坐标( x , y )都适合不等式,x^2/a^2 ≥1,y∈R所以x≥a 或x≤-a; y∈R2、对称性 x^2/a^2 -y^2/b^2 =1 (a>0,b>0),关于x轴、y轴和原点都是对称。x轴、y轴是双曲线的对称轴,原点是对称中心,又叫做双曲线的中心。3、顶点(1)双曲线与对称轴的交点,叫做双曲线的顶点 .顶点是A_1 (-a,0)、A_2 (a,0),只有两个。(2)如图,线段A_1 A_2 叫做双曲线的实轴,它的长为2a,a叫做实半轴长;线段B_1 B_2 叫做双曲线的虚轴,它的长为2b,b叫做双曲线的虚半轴长。(3)实轴与虚轴等长的双曲线叫等轴双曲线4、渐近线(1)双曲线x^2/a^2 -y^2/b^2 =1 (a>0,b>0),的渐近线方程为:y=±b/a x(2)利用渐近线可以较准确的画出双曲线的草图
问题导学类比用方程研究椭圆双曲线几何性质的过程与方法,y2 = 2px (p>0)你认为应研究抛物线的哪些几何性质,如何研究这些性质?1. 范围抛物线 y2 = 2px (p>0) 在 y 轴的右侧,开口向右,这条抛物线上的任意一点M 的坐标 (x, y) 的横坐标满足不等式 x ≥ 0;当x 的值增大时,|y| 也增大,这说明抛物线向右上方和右下方无限延伸.抛物线是无界曲线.2. 对称性观察图象,不难发现,抛物线 y2 = 2px (p>0)关于 x 轴对称,我们把抛物线的对称轴叫做抛物线的轴.抛物线只有一条对称轴. 3. 顶点抛物线和它轴的交点叫做抛物线的顶点.抛物线的顶点坐标是坐标原点 (0, 0) .4. 离心率抛物线上的点M 到焦点的距离和它到准线的距离的比,叫做抛物线的离心率. 用 e 表示,e = 1.探究如果抛物线的标准方程是〖 y〗^2=-2px(p>0), ②〖 x〗^2=2py(p>0), ③〖 x〗^2=-2py(p>0), ④
二、直线与抛物线的位置关系设直线l:y=kx+m,抛物线:y2=2px(p>0),将直线方程与抛物线方程联立整理成关于x的方程k2x2+2(km-p)x+m2=0.(1)若k≠0,当Δ>0时,直线与抛物线相交,有两个交点;当Δ=0时,直线与抛物线相切,有一个切点;当Δ<0时,直线与抛物线相离,没有公共点.(2)若k=0,直线与抛物线有一个交点,此时直线平行于抛物线的对称轴或与对称轴重合.因此直线与抛物线有一个公共点是直线与抛物线相切的必要不充分条件.二、典例解析例5.过抛物线焦点F的直线交抛物线于A、B两点,通过点A和抛物线顶点的直线交抛物线的准线于点D,求证:直线DB平行于抛物线的对称轴.【分析】设抛物线的标准方程为:y2=2px(p>0).设A(x1,y1),B(x2,y2).直线OA的方程为: = = ,可得yD= .设直线AB的方程为:my=x﹣ ,与抛物线的方程联立化为y2﹣2pm﹣p2=0,
1.判断 (1)椭圆x^2/a^2 +y^2/b^2 =1(a>b>0)的长轴长是a. ( )(2)若椭圆的对称轴为坐标轴,长轴长与短轴长分别为10,8,则椭圆的方程为x^2/25+y^2/16=1. ( )(3)设F为椭圆x^2/a^2 +y^2/b^2 =1(a>b>0)的一个焦点,M为其上任一点,则|MF|的最大值为a+c(c为椭圆的半焦距). ( )答案:(1)× (2)× (3)√ 2.已知椭圆C:x^2/a^2 +y^2/4=1的一个焦点为(2,0),则C的离心率为( )A.1/3 B.1/2 C.√2/2 D.(2√2)/3解析:∵a2=4+22=8,∴a=2√2.∴e=c/a=2/(2√2)=√2/2.故选C.答案:C 三、典例解析例1已知椭圆C1:x^2/100+y^2/64=1,设椭圆C2与椭圆C1的长轴长、短轴长分别相等,且椭圆C2的焦点在y轴上.(1)求椭圆C1的半长轴长、半短轴长、焦点坐标及离心率;(2)写出椭圆C2的方程,并研究其性质.解:(1)由椭圆C1:x^2/100+y^2/64=1,可得其半长轴长为10,半短轴长为8,焦点坐标为(6,0),(-6,0),离心率e=3/5.(2)椭圆C2:y^2/100+x^2/64=1.性质如下:①范围:-8≤x≤8且-10≤y≤10;②对称性:关于x轴、y轴、原点对称;③顶点:长轴端点(0,10),(0,-10),短轴端点(-8,0),(8,0);④焦点:(0,6),(0,-6);⑤离心率:e=3/5.
二、典例解析例5. 如图,一种电影放映灯的反射镜面是旋转椭圆面(椭圆绕其对称轴旋转一周形成的曲面)的一部分。过对称轴的截口 ABC是椭圆的一部分,灯丝位于椭圆的一个焦点F_1上,片门位另一个焦点F_2上,由椭圆一个焦点F_1 发出的光线,经过旋转椭圆面反射后集中到另一个椭圆焦点F_2,已知 〖BC⊥F_1 F〗_2,|F_1 B|=2.8cm, |F_1 F_2 |=4.5cm,试建立适当的平面直角坐标系,求截口ABC所在的椭圆方程(精确到0.1cm)典例解析解:建立如图所示的平面直角坐标系,设所求椭圆方程为x^2/a^2 +y^2/b^2 =1 (a>b>0) 在Rt ΔBF_1 F_2中,|F_2 B|= √(|F_1 B|^2+|F_1 F_2 |^2 )=√(〖2.8〗^2 〖+4.5〗^2 ) 有椭圆的性质 , |F_1 B|+|F_2 B|=2 a, 所以a=1/2(|F_1 B|+|F_2 B|)=1/2(2.8+√(〖2.8〗^2 〖+4.5〗^2 )) ≈4.1b= √(a^2 〖-c〗^2 ) ≈3.4所以所求椭圆方程为x^2/〖4.1〗^2 +y^2/〖3.4〗^2 =1 利用椭圆的几何性质求标准方程的思路1.利用椭圆的几何性质求椭圆的标准方程时,通常采用待定系数法,其步骤是:(1)确定焦点位置;(2)设出相应椭圆的标准方程(对于焦点位置不确定的椭圆可能有两种标准方程);(3)根据已知条件构造关于参数的关系式,利用方程(组)求参数,列方程(组)时常用的关系式有b2=a2-c2等.
二、探究新知一、空间中点、直线和平面的向量表示1.点的位置向量在空间中,我们取一定点O作为基点,那么空间中任意一点P就可以用向量(OP) ?来表示.我们把向量(OP) ?称为点P的位置向量.如图.2.空间直线的向量表示式如图①,a是直线l的方向向量,在直线l上取(AB) ?=a,设P是直线l上的任意一点,则点P在直线l上的充要条件是存在实数t,使得(AP) ?=ta,即(AP) ?=t(AB) ?.如图②,取定空间中的任意一点O,可以得到点P在直线l上的充要条件是存在实数t,使(OP) ?=(OA) ?+ta, ①或(OP) ?=(OA) ?+t(AB) ?. ②①式和②式都称为空间直线的向量表示式.由此可知,空间任意直线由直线上一点及直线的方向向量唯一确定.1.下列说法中正确的是( )A.直线的方向向量是唯一的B.与一个平面的法向量共线的非零向量都是该平面的法向量C.直线的方向向量有两个D.平面的法向量是唯一的答案:B 解析:由平面法向量的定义可知,B项正确.
(1)吾尝(曾经)终日而思矣,不如须臾(片刻)之所学也;吾尝肢(踮起脚跟)而望矣,不如登高之博见(看得广)也。(学、思对比,强调了学习的作用;跛望与登高对比,登高的收获大。两例证明利用学习、利用外物的作用。)(2)登高而招(招手),臂非加长也,而见者(看的人)远(远也看得见);顺风而呼(呼喊),声非加疾(快)也,而闻者(听的人)彰(听得更清楚)。(两例证明利用自然条件的作用。)(3)假(借助)舆马者(的人),非利足(快脚)也,而致(达到)千里;假舟楫者,非能水(善游)也,而绝(横渡)江河。(两例证明利用工具的作用。)(4)君子生(性)非异也,善假(利用)于(对)物(外物)也。连用比喻,得出结论:那些有才德的君子,生来本性与普通人没有什么两样(生非异也),只是由于他善于利用学得的知识和本领,善于利用处界条件弥补自身的不足,不断提高自己,所以才成为君子的。
评价分析法,就是引述事例后,对所引述的事例作适当的评价,从而使自己的观点得到印证。例如,在论“节俭”时,引用了“曾国藩以俭戒子,其子曾纪泽终成出色的外交家;方志敏居官不贪,一生清贫,千古留名”的事实后,接着进行分析:是的,“俭者心常富”,节俭能培养人同困难作斗争的勇气和意志,而这正是一个人立业最重要的素质。从这个意义上说,有人说饥饿是人生的佐料,吃苦是一种资本也不无道理,而自觉和戒奢尚俭则更是促人修身养性,磨炼意志的有效途径。这里,作者紧扣论点,对论据进行了评价性分析,这种评价分析使作者的观点得到强化。(四)因果分析法因果分析法,就是抓住论据所述的事实,并据此推求形成原因的一种分析方法。事出必有其因。我们可以依据事物发展变化的因果关系,由事物发展变化的结果,推导出产生这种结果的原因,从而揭示出一定的生活规律,使事例有力地证明观点。
全班齐读第五段内容。请一位同学分析,接着让这位同学按他分析的读一遍。3、4两自然段的平缓之后,第5段作者的情感再次抬升。为了满足这种情感的张扬,作一口气连用了四个排比句式“现在是……时候”,一方面这是情感发泄的需要,另一方面这种排山倒海的语势也加强了内容的表达,极强地突出了现实为自由、平等而战的重要性。四、学会演讲我们刚才细读了课文,但读和讲是有区别的。所谓演讲,是一门语言艺术,它的主要形式是“讲”,即运用有声语言并追求言辞的表现力和声音的感染力;同时还要辅之以“演”,即运用面部表情、手势动作、身体姿态乃至一切可以理解的态势语言,使讲话“艺术化”起来,从而产生一种非凡的艺术魅力。那么,接下来就假设一下假如你是马丁·路德·金,你会怎样去讲这篇演讲辞。
教材分析改革开放后我国的综合国力不断增强,人民对祖国统一的愿望越来越迫切。本节课以“一国两制”构想的提出,香港、澳门的回归和海峡两岸关系的发展为中心,说明实现祖国统一,完成中华民族复兴是历史发展的必然。第一目“‘一国两制’构想的提出”主要讲述了“一国两制”的含义及历史意义。第二目“香港、澳门的回归”着重讲述了香港回归、澳门回归的经过及历史意义,这是“一国两制”成功的实践。第三目“海峡两岸关系的发展”讲述了大陆注重发展与台湾的关系,促进海峡两岸的经济文化交流与合作,打破了几十年来海峡两岸的隔绝状态,促进了祖国统一的进程。此外,教材还通过“资料回放”“历史纵横”“学思之窗”等栏目,为学生学习提供了一些详细的史料。在教学中要分析图表资料,引导学生理解完成祖国统一大业,实现中华民族的复兴,是任何人也阻挡不了的历史潮流。
The activity topic of this section is "report an ongoing event", and the structure is the passive voice of present continuous tense. Rare wild animals are suffering from large-scale poaching, and species are on the brink of danger. Rescue operations are underway. "Being" and "suffering" are the meanings of the present progressive passive voice.The usage of present progressive passive voice is of great importance in writing a good discourse and appreciating some difficult language items, so it is vital to master it and use it flexibly in a context.1. Motivate Ss to deepen the understanding of the usage of present progressive passive voice in a fixed context.2. Enable Ss to master the usage of present progressive passive voice and use it flexibly in a context.3. Lead Ss to construct sentences or appreciate sentences used master it and use it flexibly in a context.1. Help students to appreciate the function of the usage of present progressive passive voice in a sentence2. Instruct students to write essays using the proper usage of present progressive passive voice.Look at the picture and tell me what are workers doing? What is the house being done?
1. 标题首先根据海报的特点、格式写明标题。海报中往往把内容作为大标题。例如: Save the earth, Save the birds。2. 正文部分不同的海报其正文部分的侧重点不同。对于介绍性的海报, 首先要引出话题, 其次列出原因, 最后是总结。对于宣传类的海报, 要写明具体内容, 如: 活动内容, 地点以及参加活动的注意事项, 主持或举办单位等。1. 图片: 要选择引人注目的图片, 与主题要相关, 色彩明亮。话题句式 1. It is a treasure of our country. 它是我国的国宝。2. Believe it or not, at present only several thousand pandas exist in the world. 信不信由你, 目前世界上仅现存几千只熊猫。 3.It’s because of human activities that tigers are endangered. 正是因为人类的活动, 老虎处于濒危的状态。4. Many wild animals are in danger of dying out. 很多野生动物面临着灭绝的危险。 5. The government has taken effective measures to protect them. 政府已采取有效的措施来保护它们。6. People should raise the awareness of the protection of wild animals. 人们应该提高保护野生动物的意识。 7. It’s amazing that there are merely less than 1, 000 finless porpoises living in China. 非常令人吃惊, 目前中国仅有不足1 000只江豚。
Paragraph 3. Jan decided to start an IT club to teach old people how to use computers and the Internet. Paragraph 4. Jan has started taking online classes to learn more about how to use the Internet to make society better. Paragraph 5. Jan’s life has been greatly improved by the Internet. Step 5: Critical thinking:(1)How do you arrange your time spent on study and the Internet? Is it reasonable? I usually surf the Internet using my mobile phone for only an hour after class, and it is reasonable for me.(2)What are your online activities? Are they safe? I chat with my friends, read news and play games. I never give away my private information so I think they are safe.Step 4: summary Much has been written about the wonders of the World Wide Web. There are countless articles (1)______(tell) us how the Internet has made our lives more convenient. But the Internet has done a lot (2)_____(much) for people than simply make life more convenient. People’s lives (3) _________________(change) by online communities and social networks so far. Take Jan for example, who developed a serious illness that made her (4)_____(stick) at home with only her computer to keep (5)___(she) company. She joined an online group (6)______ she could share problems, support and advice with others. She considered the ability to remove the distance between people as one of the greatest (7)_______(benefit). She was so inspired (8)____ she started an IT club in which many people have been helped. She has started to learn more about how to use the Internet to make society better. Her next goal is to start a charity website to raise money (9)___ children in poor countries. Jan’s life has been (10)______(great) improved by the Internet. Step 5 Homework:Review what we have learned and find out the key language points in the text.
Step1:自主探究。1.(教材P52)Born(bear) in the USA on 2 January 1970, Whitacre began studying music at the University of Nevada in 1988.2.(教材P52) Moved(move) by this music, he said, “It was like seeing color for the first time.”3.(教材P56)I was very afraid and I felt so alone and discouraged(discourage).4.(教材P58)Encouraged(encourage) by this first performance and the positive reaction of the audience, I have continued to play the piano and enjoy it more every day.Step2:语法要点精析。用法1:过去分词作表语1).过去分词可放在连系动词be, get, feel, remain, seem, look, become等之后作表语,表示主语所处的状态Tom was astonished to see a snake moving across the floor.汤姆很惊讶地看到一条蛇正爬过地板。Finally the baby felt tired of playing with those toys.终于婴儿厌倦了玩那些玩具。注意:1).过去分词作表语时与被动语态的区别过去分词作表语时,强调主语所处的状态;而动词的被动语态表示主语是动作的承受者,强调动作。The library is now closed.(状态)图书馆现在关闭了。The cup was broken by my little sister yesterday.(动作)昨天我妹妹把杯子打碎了。2)感觉类及物动词的现在分词与过去分词作表语的区别过去分词作表语多表示人自身的感受或事物自身的状态,常译作“感到……的”;现在分词多表示事物具有的特性,常译作“令人……的”。
This section focuses on "learning about experiencing music Online". This virtual choir is a new form of music performance. Members from all over the world don't need to love to come to a place. Instead, they use the new technology to model the various parts and wonderful virtual harmony group of music in the family. Students need to understand the main meaning of each paragraph. Finding topic sentences is an important way to understand the general idea of a paragraph. After the topic sentence, it is usually the detail sentence that supports and explains the topic sentence. Some paragraphs have obvious subject sentences, for example, the first sentence of the second paragraph is the subject sentence of the paragraph, and the following sentenceStudents need to pay attention to the topic sentences and key sentences, and then pay attention to how the sentences after the meaning explain, explain and support the topic sentences or key sentences before.1.Guide students to learn about experiencing music online2.Guide students to scan and circle the information in the text.3.Guide students to find the numbers and dates to fill in the timeline.4.Guide students to learn more about music by completing the sentences with the correct forms of the words and phrases. And then make a mind map about the outline of the passage.1. Guide students to pay attention to reading strategies, such as prediction, self-questioning and scanning.2. Help students sort out the main meaning of each paragraph and understand the narrative characteristics of "timeline” in illustrative style.3. Lead students to understand the changes that have been caused by the Internet.
This teaching period mainly deals with grammar “restrictive relative clauses.” To begin with, teachers should lead students to revise what they have learned about the relative pronouns and relative adverbs. And then, teachers move on to stress more special cases concerning this grammar, such as the “preposition+ relative pronouns which and whom” and cases where we can omit the relative pronouns. This period carries considerable significance to the cultivation of students’ writing competence and lays a solid foundation for the basic appreciation of language beauty. The teacher is expected to enable students to master this period thoroughly and consolidate the knowledge by doing some exercises. 1. Guide students to review the basic usages of relative pronouns and adverbs of attributive clauses.2. Lead students to learn to use some special cases concerning restrictive relative clauses flexibly.2. Enable students to use the basic phrases structures flexibly.3. Strengthen students’ great interest in grammar learning.1. Help students to appreciate the function of relative pronouns and adverbs of attributive clauses in a sentence2. Instruct students to write essays using the proper relative pronouns and adverbs of attributive clauses.本节语法思考:定语从句在复合句中的作用是什么? 关系词有哪些?定语从句在复合句中的作用相当于形容词,它在句中作定语修饰名词或代词。他们在先行词和定语从句之间起到联系作用,同时在意义上代表先行词并在定语从句中担任一个成分。被定语从句所修饰的词称先行词,定语从句一般放在先行词的后面。
The theme of the reading and thinking is about “Understanding how a problem was solved”.The Listening & Speaking & Talking is about international co-work to protect the Mount Tai, in which the students from seven countries came up with many solutions even create the Mount Tai App. This section aims at showing how to solve a difficult and even tough problem about protecting the cultural heritage by the international co-work. So in this section, cultivating students’ international awareness is very clear and important. Concretely, with the economic development, how to balance the protection of cultural relics and social development is a big challenge for human. In the 1950s, the Egyptian government wanted to build the Aswan Dam across the Nile to control floods, produce electricity and water farms. But the proposal led to protests because it would destroy a lot of cultural relics. The Egyptian had no choice but ask the UN for help. Therefore, a international cooperation about how to protect the cultural relics began, which involved the time length about 20 years and a large amount of fund. Then, the problems was solved. 1. Read quickly to get the main idea and the structure of the article; read careful to get detailed information.2. Learn to use the reading strategy---making a timeline3. Learn how to solve a tough problem by asking for help and cooperation4. Have the international awareness and understand the great strength of international cooperation.1. Read quickly to get the main idea and the structure of the article; read careful to get detailed information.2. Learn to use the reading strategy---making a timeline.3. Learn how to solve a tough problem by asking for help and cooperation.
The listening and speaking part aims at how to protect and help endangered animals by listening, speaking and talking about the facts and reasons. This lesson analyzes the decreasing clause of Tibetan antelope population and the measures of protecting Tibetan antelopes. So students can be guided to learn to analyse the title and use different reading skills or strategies, like scanning, skimming and careful reading.1. Read quickly to get the main ideas and the purpose of going to Tibetan; read carefully to understand what the author see and think.2. Understand the sentences of the present continuous passive voice such as “Much is being done to protect wildlife.” and the inverted sentence “Only when we learn to exist in harmony with nature can we stop being a threat to wildlife and to our planet.”3. Enhance the awareness of protecting wildlife.4. Cultivate the reading methods according to different materials.1. Read quickly to get the main ideas and the purpose of going to Tibetan; read carefully to understand what the author see and think.2. Understand the sentences of the present continuous passive voice such as “Much is being done to protect wildlife.” and the inverted sentence “Only when we learn to exist in harmony with nature can we stop being a threat to wildlife and to our planet.”3. Cultivate the reading methods according to different materials.Step 1 Leading-inWatch a video about elephants and whales and then ask:Why are they endangered ? They are killed/hunted
This unit is about the Internet, which has a great influence to our humans and our lives. During the Listening & Speaking & Talking and Reading and Thinking section, the influence in examples has been shown. Thus, use the Present Perfect Tense is appropriate. However, in order to show the justice or weaken the doer of the behavior/action, it’s better to use the Present Perfect Passive Voice than the Present Perfect Tense. Besides, having learned to use the Present Perfect Passive Voice, students can beautify their language in their writing. 1. Learn the structure of the Present Perfect Passive Voice and its functions. 2. Learn to change the sentences with the Present Perfect Passive Voice into the sentences with the Present Perfect Passive Voice. 3. Learn to write sentences with the Present Perfect Passive Voice flexibly according to the context. 1. Learn the structure of the Present Perfect Passive Voice and its functions. 2. Learn to change the sentences with the Present Perfect Passive Voice into the sentences with the Present Perfect Passive Voice. 3. Learn to write sentences with the Present Perfect Passive Voice flexibly according to the context. Step 1 Observe the following sentences, then change the sentences into passive voice.He has been selected to take part in the sports meeting.(肯定句)他已被挑选出来参加运动会。The ink has not been removed from his overcoat.(否定句)墨迹还没有从他外套上去掉。
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