[仁爱版七年级上册英语教案教学反思]仁爱版七年级上册英语教案：LookingDifferent

Unit 2 Looking Different
Topic 1 I have a small nose.
Section A
The main activities are 1a, 2a and 3a. 本课重点活动是1a, 2a和3a。
Ⅰ.Teaching aims and demands 教学目标
1.Learn some new words:
(1)Learn words about parts of the body:
nose, eye, head, face, hair, ear, mouth, neck
(2)Learn some other new words:
guess, have, small, has, big, know, right, round, long, wide, girl, boy, short
2. Learn some useful sentences:
(1)Oh, I know.
(2)Yes, you’re right.
3. Learn the simple present tense with“have/has”and adjectives of description:
(1)I have a big nose.
(2)They have round faces.
(3)She has long hair.
(4)It has big ears.
4. Learn how to describe people’s appearances.
Ⅱ. Teaching aids 教具
小黑板/影片的封面或图片/教学挂图/录音机
Ⅲ. Five-finger Teaching Plan 五指教学方案
Step 1 Review 第一步 复习(时间:10分钟)
通过复习，培养学生根据图画和文字信息进行简单交流的能力。
(出示小黑板上的图画和文字信息，师生进行互动问答，然后让学生两人一组表演对话。复习描述人的基本情况。)
Name: Jane
Age: 12
From: Canada
School: Beijing Ren’ai International School
Class: Four
Grade: Seven
Phone number: (010)9267-6929

(1)T: What’s her name?
S1: Her name is Jane.
T: How old is she?
S2: She is twelve.
T: Where is she from?
S3: She is from Canada.
T: What class is she in?
S4: She is in Class Four, Grade Seven.
T: What’s her telephone number?
S5: It’s (010)9267-6929.
(把全班学生分成两组就此对话进行表演。)
(2)(根据图画导入新内容。)
T: Well done! Now we have learned something about Jane. Do you like her? Is she beautiful? Then how to describe her appearance? First, let’s learn some new words about parts of the body. Now let’s look at the picture.
Step 2 Presentation 第二步 呈现(时间:12分钟)
利用图片，借助体态语，帮助学生学习语言，并培养他们的观察能力。
1. (教师利用Jane的图片教授2a中人体部位的名称，并在图片的相应位置板书单词，然后领学生拼读。注：教师应按照从上到下、从局部到整体的顺序讲授人体部位，以便帮助学生记忆。)
T: Please listen and follow me, then touch the parts of your body when you say them. Please go!
(板书生词，要求学生掌握，并让学生注意拼读。)
head face hair eye ear nose mouth neck
2. (利用2a的教学挂图，操练表示人体部位的名词。)
T: Let’s look at this picture. What’s this?(手指画着头部的图片。) S1, please.
S1:Head.
T: How do you spell it, please?
S1:H-E-A-D, head.
(以同样方式操练其他表示人体部位的名词。)
3. (以做游戏的方式呈现新单词和短语，使学生易于理解和接受。具体方法如下：把全班学生分成四组，每组轮流选出一名学生在黑板上画人物头像。每个学生画一个身体部位。例如，第一个学生画的是一张圆脸，教师就帮助学生说a round face。板书并解释。其他身体部位以同样方式呈现。直到把所有本节课所涉及的描述性形容词都呈现出来为止。可以多画几幅图，完成后，每组学生轮流用短语描述人物外貌特征，说得准确流利者为胜。)
T: Nice work, boys and girls. Now let’s play a game. I’ll divide you into four groups. Each group chooses a student to draw a part of the body. And you should describe it with a phrase. OK. Let’s begin!
(板书boy和girl，并要求学生掌握。)
boy, girl
S2: (画一个圆脸) A round face. (教师帮助学生说。)
(板书并解释，要求学生掌握。)
round
S3: (画一双小眼睛) Small eyes.(教师帮助学生说。)
(板书并解释，要求学生掌握。)
small
S4: (画一个大鼻子) A big nose.(教师帮助学生说。)
(板书并解释，要求学生掌握。)
big
…
(以同样方式呈现a wide mouth, big ears, long hair，要求学生掌握。)
4. (出示3a的教学挂图，让学生观察图片中突出的外貌特征，巩固表示人体部位的名词和部分形容词。)
T: OK, now look at these pictures. Let’s talk about their different looks. Is this nose big?(教师指着图片1的鼻子，并借助手势问。)
Ss: Yes. It’s big.(引导学生说。)
T: Good. He has a big nose. Are they big, too?(教师指着图片②问。)
Ss: No.
T: Very good. They are not big. They are small. They have small noses and small eyes.(教师指着图片2的鼻子和眼睛说。)
(以同样方式操练其他四幅图片。)
5. (在熟练掌握人体部位和描述人体部位形容词的基础上，结合3a的教学图片，让学生操练形容词+人体部位的短语，然后教授have和has的用法，进而过渡到完整的句子。)
(教师说出一个人称代词，让学生结合3a的教学挂图说出用have还是用has。)
T: Next, please practice the sentence patterns. I say personal pronouns, you complete the sentences.
T: Look at Picture 1. “I …”
Ss: I have.
T: The whole sentence.(“完整的句子”)
Ss: I have a big nose.
T: Picture 2. “We …”
Ss: We have ...
(教师示意说完整的句子。)
Ss: We have small eyes.
T: Picture 3.“They …”
Ss: They have …(教师帮助说)
(教师示意说完整的句子。)
Ss: They have round faces.
…
6. (播放3a录音，让学生跟读并注意语音语调。)
T: Listen to 3a and repeat. Pay attention to the pronunciation and intonation.
7. (1) (总结have/has的用法并板书。)
T: Let’s sum up the usages of“have”and“has”.
① have: S(I/We/You/They) +have …
② has: S(He/ She/ It)+has …
(2) (教师带领学生运用身边的实物，练习用have/has造句。)
T: I have a book.
She has a big pencil-box.
He has a beautiful bag.
…
Step 3 Consolidation 第三步 巩固(时间:8分钟)
完成3b和4。通过小组竞赛，接龙游戏，替换练习等活动，进一步操练have，has的用法。
1. (小组竞赛。限定时间要求学生书面完成3b。核对答案，并让学生复述have/has的用法，最后让学生齐读这七个句子。)
T: Now, let’s P.K. Can you complete the sentences in 3b on Page 26 as quickly as you can? Then I’ll divide you into two teams. Boys must choose the sentences which they use “have”. Girls must choose the sentences which they use “has”. Please go.
2. (接龙游戏。教师根据自己的实际情况以第一人称说一个句子，学生模仿练习。)
T: Well done. Now let’s play a game in chains. You can say a sentence to describe yourself. Please use “I have” to make sentences, for example, I have a big nose. Begin!
S1: I have a small nose.
S2: I have a long face.
S3: I have a big head.
S4: …
…
3. (根据学生的描述，有意识板书一些句型，运用肢体语言，引导学生进行替换练习。)
T: Nice work. Huang Lin and Huang Hao, please.
Huang Lin: I have a small nose.
Huang Hao: I have a small nose.
T: You can say together like this: We have …
Huang Lin and Huang Hao: We have small noses.
T: And the whole class can say like this: They have …
Ss: They have small noses.
Huang Lin: I have a small nose.
Huang Hao: I have a small nose.
(引导他们用we来描述，注意单复数形式，其他同学用they转述。教师板书。)
Huang Lin and Huang Hao: We have small noses.
Ss: They have small noses.
(引导其他同学来描述，教师板书。)
Lin Ying(女): I have long hair.
Ss: She has long hair.
Chen Bin(男): I have big ears.
Ss: He has big ears.
4. (请学生根据描述，完成4。)
T: Read the passages and draw pictures.
5. (两人一组，一位描述，另一位画，画完后同桌交流。评选出优胜小组并将其画贴在墙上，以资鼓励。)
T: Let’s draw a picture in pairs. One reads, the other draws. Are you ready?
Ss: Yes.
T: Let’s begin.
S5: This girl has a round face, big eyes …
S6: (根据S5的描述，画女孩的面部特征。)
…
Step 4 Practice 第四步 练习(时间:8分钟)
完成1a，1b，2a和2b，进一步帮助学生巩固本课的功能项目，培养学生的听说能力。
1. (用学生画得较好的图片进行问答，问答过程中教师板书新内容，并进行简单解释。)
T: Nice work. Do you know the boy? He has a round face, big eyes, a small nose, a wide mouth and small ears. His hair is short. He is a boy in Group Three. Can you guess?
Ss: Cheng Long.
T: Yes, you’re right.
(板书，并要求学生掌握。)
guess
know
I know.
right
You’re right.
2. (播放1a录音，请学生跟读并注意语音语调，然后判断下列问题的正（T）误（F）。)
T: Listen to 1a and repeat. Pay attention to the pronunciation and intonation. Then mark the following sentences True (T) or False (F).
(1)Michael has a big nose. ( )
(2)Kangkang has a small nose. ( )
3. (让学生戴上面具两人一组表演，完成1b。)
T: Now practice the dialog and then I’ll ask two students to act it out.
4. (看2a部分，用适当的形容词描述人体部位的特征。)
5. (学生两人一组进行表演，完成2b。)
T: Listen to your partner and touch the parts of your body he/she says.
S1: Touch your nose.
S2: (按S1指令做出相应动作。)
…
Step 5 Project 第五步 综合探究活动(时间:7分钟)
通过综合探究活动，使学生能够在真实的语境中锻炼口头表达的能力。同时启发学生的思维，培养他们的观察力。
1. (教师分别请一男生、一女生到黑板前，请下面的学生描述他们的外貌，教师先示范，然后以滚雪球的方式继续活动。)
(1) T: This boy has a round face.
S1: He has a round face and small eyes.
S2: He has a round face, small eyes and a big nose.
S3: …
(2) T: This girl has long hair.
S4: She has long hair and a big nose.
S5: She has long hair, a big nose and a small mouth.
S6: …
2. (听音辨人。从所听语段中获取相关信息，并作出判断。)
T: Let’s play a guessing game. Listen carefully. He is a boy in Group Five. He has big eyes and big ears. He has a wide mouth and a big head. He has a small nose and long hair. Who is he?
S7: Lin Wen.
T: No.
S8: Lin Fen.
T: Yes, you’re right.
(掌声鼓励。)
(分组进行听音辨人游戏。)
T: Now I’ll divide our class into four groups. Do as I do, please.
…
3. Homework:
(1)复习Section A。
(2)预习Section B生词。
(3)描述一位朋友的外貌。
板书设计：
I have a small nose.
Section A
1. I know.
2. You’re right.
3. (1)I have a big nose.
(2)We have small eyes.
(3)They have round faces. I/We/You/They + have …
(4)She has long hair. He/She/It + has …
(5)He has a wide mouth.
(6)It has big ears.
Section B
The main activities are 1a, 3 and 4. 本课重点活动是1a、3和4。
Ⅰ. Teaching aims and demands 教学目标
1. Learn some new words:
favorite, movie, star, Chinese, again, look, arm, hand, leg, foot
2. Learn some useful sentences:
(1)—Who is your favorite movie star?
—It’s Bruce Lee.
(2)Guess again.
3. Continue to learn the description of people’s appearances:
(1)Her eyes are small.
(2)She has a small face, big eyes and a small nose.
4. Continue to learn the simple present tense with have/has:
(1)—Does he have long hair?
—No, he doesn’t.
(2)—Does he have a wide mouth?
—Yes, he does.
Ⅱ. Teaching aids 教具
教学挂图/录音机/学生照片/小黑板
Ⅲ. Five-finger Teaching Plan 五指教学方案
Step 1 Review 第一步 复习(时间:9分钟)
通过复习上节课的目标语言，引出并学习本节课新句型。训练学生的口头表达能力。
1. (检查上节课布置的课外作业。教师把学生分成十二个小组，让学生在小组内描述他的一个朋友，然后请两个学生向全班同学描述。教师要及时给予表扬。)
T: Hello, boys and girls. From last period, we learnt how to describe someone’s appearance. Now I’ll divide our class into twelve groups. Then you talk about your friend’s looks in groups. You can begin like this: I have a friend. He is a boy. He has … And then I will choose two of you to report it in the front.
2. (教师出示28页5a的教学挂图，请八名学生依次到黑板前，按教师指令，触摸玩具的身体部位，并要求学生在黑板上写出相对应的单词。)
T: Very good! Next, look at the doll. I’ll ask eight students to come to the blackboard one by one. Please touch and write down the names of the parts of the body on the blackboard. Do you understand?
Ss: Yes.
T: Touch her hair.
Touch her face.
…
(复习学过的身体部位的名词后，教师指着图片教授并板书新单词arm, hand, leg, foot, 同时强调foot的复数形式是feet。在学生会读并理解词义后，教师继续发出指令，让所有学生做相应的动作。)
T: Great! Let’s go on learning other parts of the body. When I read, please touch the parts of your body. Please go!
T: Touch your arm.
Touch your hand.
Touch your leg.
Touch your foot.
(教师板书并要求学生掌握。)
arm, hand, leg, foot, feet
3. (教师利用5a的教学挂图继续问答，导入本课新句型。)
T: Look at the doll. Does she have long hair? (教师引导学生回答。)
Ss: Yes, she does.
T: Does she have small eyes? (教师引导学生回答。)
Ss: No, she doesn’t.
(板书并要求学生理解。)
does Does she have …
Yes, she does.
doesn’t No, she doesn’t.
(教师示范后，请学生用上面的句型就其他身体部位进行问答练习。)
T: Well, now practice the drills above one by one. One asks, the other answers. Please go!
S1: Does she have big ears?
S2: No, she doesn’t.
S3: Does she have a small mouth?
S4: Yes, she does.
…
Step 2 Presentation 第二步 呈现(时间:10分钟)
通过1a对话，使学生初步掌握动词have/has的一般疑问句及其肯定和否定回答，并学习新句型Who’s your favorite …?。
1. (教师在黑板上画一颗星星。)
T: This is a star.
(在星星下方板书star，引导学生推测出词义，并要求学生掌握。)
star
(继续板书movie star。)
movie star
T: 《赤壁》is a nice movie.《功夫熊猫》is a movie, too. Can you guess what’s the meaning of“movie”?
Ss: 电影。
T: Nice work. What’s the meaning of “movie star”?
Ss: 电影明星。
T: Good! Who is your favorite movie star?
(板书并要求学生掌握。)
favorite
(采访两三位学生，说出他们最喜爱的电影明星是谁，导入1a。)
2. (出示1a教学挂图。)
T: You all have your own favorite movie stars. Who is Michael’s? Do you want to know about him? (指着图片。)
T: This is Michael’s favorite movie star. Can you guess who he is? S1, please.
S1: Li Lianjie.
T: No. Li Lianjie is my favorite movie star. Guess again. S2, please.
S2: Bruce Lee.
T: No. He is from China. He is Chinese and has a big nose. OK. Now listen to 1a and guess again. Who’s Michael’s favorite movie star?
(板书Chinese和again，要求学生掌握。)
Chinese, again
3. (学生听录音猜测图片上的人物，教师鼓励他们谈论自己最喜爱的电影明星，可让同桌两人一组进行操练。)
T: Who’s he? S3, please.
S3: He’s Cheng Long.
T: Yes. You’re right. Now practice the dialog in pairs like this:
S4: Who is your favorite movie star?
S5: My favorite movie star is Li Lianjie./It’s Li Lianjie. He is tall and strong …
…
4. (再播放1a录音，请学生跟读并注意语音语调。)
T: Listen again and repeat. Pay attention to your pronunciation and intonation.
Step 3 Consolidation 第三步 巩固(时间:10分钟)
通过听说读写的练习，强化动词have/has的用法及描述人的外貌特征的方法。
1. (让学生完成1b，巩固1a。)
T: OK, just now, you talked about your favorite movie star. Can you talk something about your favorite teacher with your partner? You can use the sentences: “Who is your favorite teacher?” “Guess, he’s …” “Does he have …?” “No. Guess again.”
2. (教师拿出准备好的学生照片说：“假定这位学生是你的朋友，请根据1a，表演对话。)
T: Suppose this is your good friend, Lin Wen. Make a similar conversation according to 1a, and act it out.
S1: I have a good friend in my class. Guess who is my favorite friend?
S2: Is your friend a girl?
S1: Yes, she is. She has a big nose.
S2: Does she have long hair?
S1: Yes, she does.
S2: Does she have small eyes?
S1: No, she doesn’t. Her eyes are big.
S2: Is she Lin Wen?
S1: Yes, you are right.
3. (看2部分，听录音填数字，要求学生使用has句型进行核对。做得好的给予掌声鼓励。完成2。)
T: Nice work. Now let’s look at the kids with masks on Page 27. They’re Maria, Michael, Wang Junfeng, Kangkang, Linda and Jane. Can you guess what they look like? Next, please listen to 2 and match the following phrases with the right numbers. Then describe the kids with the sentence patterns: Maria has a small mouth. She has a small mouth.（核对答案时教师可以有意识地用be动词来重复学生的答案，并板书。)
T: OK. Let’s check your answers one by one. S3, please.
S3: Kangkang has a big head. He has a big head.
T: Yes. That’s right. His head is big. S4, please.
S4: Jane has a small face. She has a small face.
T: Right. Her face is small. S5, please.
S5: Wang Junfeng has small eyes. He has small eyes.
T: Good. His eyes are small. S6, please.
S6: Linda has long hair. She has long hair.
T: Very good. Her hair is long.
(板书句型，引导学生使用be动词来描述人物的外貌特征，并提醒学生注意人称代词主格和形容词性物主代词之间的替换。)
He has big eyes.→His eyes are big.
She has long hair.→Her hair is long.
T: Well. What about Kangkang? S7, please.
S7: Kangkang has a big nose. He has a big nose.
T: Is that right?
Ss: Yes. His nose is big.
T: Good. Now let’s practice the drills with your partner.
(根据黑板上的信息，让学生使用be动词描述2中人物的外貌特征。)
Example:
I have a round face.→My face is round.
4. (教师利用简笔画或图片帮助学生完成3。教师可向学生说明描述人的外貌有多种方式并要求学生掌握。)
T: Look at me. My face is round./I have a round face. Now look at the picture in 3 on Page 28 and rewrite the sentences using have or has. Then make more sentences. Finish 3.
Step 4 Practice 第四步 练习(时间:8分钟)
让学生听录音，模仿语音语调，为学生的口语交际打下良好的语音基础，完成4。完成5a，5b，进一步巩固身体部位的名称，通过游戏活跃课堂气氛，激发学生学习英语的兴趣。
1. (听4录音，教师要求学生学会判断和标注升降调。完成4。)
T: Listen to 4 and learn how to judge and mark the intonation.
A: Who’s that girl?
B: She’s my friend, Mary.
A: Look, she has a small face, big eyes and a small nose.
B: That’s right.
(板书look，要求学生掌握。)
look
2. (听1a，标出升降调。练习语音语调。然后核对答案。)
T: Listen to 1a and mark the intonation.
3. (完成5b，巩固5a。教师说明游戏规则：当听到Bobby says时才能做动作。把学生分成四大组，先小组操练后每组选出一名代表上讲台，由教师发出指令，四名学生做动作，做错的淘汰，选出最终获胜者，教师给予奖励。)
Step 5 Project 第五步 综合探究活动(时间:8分钟)
通过真实的任务，帮助学生熟练运用本课所学的目标语言。
1. (做猜谜游戏。)
(这个游戏是通过问与答来猜测对方的要好朋友。游戏内容：一位同学事先在纸上写下同班中要好同学的姓名，折好交给另一个同学，让这位同学猜测到底是谁，允许这位同学提三个有关外表的问题，然后通过回答判断，最后打开纸张看是否猜对。)
T: OK. Let’s begin.
S1: I have a good friend in our class. He is a boy. Guess! Who?
S2: Does he have a big head?
S1: Yes, he does.
S2: Does he have small eyes?
S1: No, he doesn’t.
S2: Does he have a round face?
S1: Yes, he does.
S2: He is Lin Jing.
S1: Yes, you’re right. Great!
(如果回答为No，就打开纸张核对。然后同桌间继续进行猜谜游戏。)
2. (以My favorite teacher/classmate/friend/…为题，要求学生试用3中的不同句式描述人物的外貌特征。)
3. Homework:
(1)与同伴练习会话1a。
(2)复习Section A和Section B的单词。
(3)预习Section C单词。
(4)根据1a及3中的句式编对话。
板书设计：
I have a small nose.
Section B
1.—Does he have long hair? 2. Who is your favorite movie star?
—No, he doesn’t. It’s Bruce Lee.
—Does he have a wide mouth? Guess again.
—Yes, he does. 3.①Her hair is long. = She has long hair.
②His eyes are big. = He has big eyes.
Section C
The main activities are 1a and 2. 本课重点活动是1a和2。
Ⅰ. Teaching aims and demands 教学目标
1. Learn some new words and phrases:
come, come from, student, sister, different, knife, don’t=do not
2. Continue to learn the simple present tense with“have/has”:
(1)Do you have a knife?
Yes, I do.
(2)Do they have long legs?
No, they don’t. They have short legs.
(3)Does he have a ruler?
Yes, he does.
3.(1)Talk about the introduction and review the description of people’s appearances:
①I come from England.
②I’m a student.
③I have a sister.
④She has a round face, big eyes, a small nose and a small mouth.
(2)Talk about the similarity and differences:
We are in the same school, but in different grades.
Ⅱ. Teaching aids 教具
小黑板/纸/录音机/实物/小刀/图片
Ⅲ. Five-finger Teaching Plan 五指教学方案
Step 1 Review 第一步 复习(时间:10分钟)
通过复习，巩固表示人体部位的单词，提高学生的表达能力。
1.(教师出示一块小黑板，同时叫学生拿出预先准备好的纸和笔，先看示范，然后在纸上作图：head, hair, nose, mouth, ears, eyes, legs, arms, feet。注:可以画出不同的姿势，学生边画边用英语说出所画部位，教师巡视并督促学生大声说出单词，然后在全班范围内对所画的图进行介绍，如big eyes, a small nose, a wide mouth等。)
T: Let’s draw a picture of the people. Take out your paper and pens, and follow me. Begin! Head.
Ss: Head.(让学生边画边说。)
T: Hair.
Ss: Hair.
(复习巩固表示人体部位的单词，最后展示画得的，并给予鼓励。)
2. (1)(教师让两个学生以“Who is your favorite friend in your class?”为话题，根据Section B中的1a编对话并表演。)
T: Make a conversation to talk about“Who is your favorite friend in your class?”. Please go.
S1: Oh, I have a good friend in our class.
S2: A boy?
S1: No. She is a girl. She has a big nose.
S2: Does she have long hair?
S1: No, she doesn’t. She has short hair.
S2: Does she have small eyes?
S1: No, she doesn’t. Her eyes are big.
S2: Is she Hu Xue?
S1: Yes, you’re right.
(2)(利用学生的表演内容，师生互动问答，导入新句型。)
T: Come to the front, please, Hu Xue.
Hu Xue: OK!
T: Can you introduce yourself including your appearances?
Hu Xue: OK! My name is Hu Xue. I’m a girl. I’m thirteen years old. I’m from China. I have a big nose and big eyes. My hair is short.
T: Great. Are you a Chinese teacher?
Hu Xue: No. I’m not a teacher, but I’m a …
T: Good. You’re not a teacher. You’re a student. Do you have a big nose?
Hu Xue: Yes, I do.(教师帮助学生回答“I do”)
T: Do you have small eyes?
Hu Xue: No, I don’t.(教师帮助学生回答don’t，并说明don’t=do not。)
T: Do you have a sister?
Hu Xue: Yes, I do.
T: Are you in the same school?
Hu Xue: No, we’re not in the same school.
T: Good. You can also say “we’re in different schools”. Do you come from China?
Hu Xue: Yes, I do.
T: Thank you. Go back to your seat and sit down.
(板书生词，分析并强调相近或相反的词、词组，加快记忆。然后带领学生朗读并要求掌握，板书新句型。)
student (teacher) Do you have …?
sister (brother) Yes, I do.
different (same) Do you have small eyes?
come from=be from No, I don’t.
do/don’t（=do not）
3. (教师通过介绍，导入1a，并设置听力任务。)
T: I know a boy. He has a sister. Do you want to know what the boy and his sister look like? Now listen to 1a.
Step 2 Presentation 第二步 呈现(时间:7分钟)
学习1a，培养学生的阅读理解能力。
1. (让学生听1a录音，然后回答问题。)
T: Listen to the tape carefully, and then answer the questions.
(板书)
(1) Is the boy a student?
(2) How old is his sister?
(核对答案)
T: Is he a student?
Ss: Yes, he is.
T: Right. How old is his sister?
Ss: Twelve.
T: Yes. You’re right. Now listen again and repeat. When you’re reading, you can underline the key words.
2. (根据短文里的关键词，完成1b，巩固1a所学知识。)
(找出正确图片后，让学生归纳描述人物外貌特征的关键词语并板书。)
T: Please find the key phrases in 1a.

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