英语九年级上册Lesson 29 DNA—The Story of You优质学案设计

Lesson 29  DNA－The Story of You   导学案

【学习目标】

1.重点单词:

DNA,blueprint,general,complex,twin,repeat,pattern,identify,related，grandson,

granddaughter,instruction

2.重点词组: in general,except for,be related to,billions of

3.重点句式:

(1) Except for some twins, every living thing has its own unique DNA.

(2) From your DNA, scientists can identify not only you, but also people who are related to you.

【重点难点】

1. 重点：掌握重点短语和句型

2. 难点：except , except for 与 besides 的用法辨析。

【导学过程】

一、课前预习

核心单词

1. ________ adj. 一般的；普遍的 2. ________ v. 重复；复述；背诵

3. ________ n. 孙子；外孙 4. ________n. 孙女；外孙女

5. ________n. 指示；说明 6. blueprint n. ________

7. complex adj. ________ 8. twin n. ________

9. pattern n. ________ 10. identify v. ________

11. related adj. ________

单词变形

pattern→________(近义词)

二、课堂学习

Step 1. 自主探究，合作交流

1．What is a blueprint?

2．Which is more complex, building a living thing or building a house?

3．Do some twins have the same DNA?

4．Is it possible to change your DNA?

5．Whose DNA is related to yours?

Step 2. 交流展示

1. copy作_________________，意为“复制品、一本、一册”，复数形式是____________。

作_________________，意为“复制、抄写”，后加______________作宾语。

   1) 你抄写完单词了吗？

Have you finished_______________the words?

   2) We don’t need any ____________（复制品）. Write them by hand.

2. But building a living thing is far more complex than building a house.

但是构建一个有生命的东西比建一座房子复杂得多。

比较级前可以用_________,________still, far, a bit, a little, a lot 等词加以修饰。

 1) --- This kind of watch is much _____ today than last month. Would you like to have one?

   --- Really? I’ll take one.

A. the most expensive   B. the cheapest    C. more expensive   D. cheaper

  2) This book is_________________than that one.这本书比那本书有趣得多。

3. From your DNA, scientists can identify not only you, but also people who are related to you.

根据你的DNA, 科学家不仅能辨别出你，而且能辨别出与你有关系的人。

not only…but also…是连词，意思是“不但……而且……”，它可以连接句中句子成分相同的部分，如果用它连接主语时，谓语动词应该以________________为准。

 Not only Jam but also his parents______a few interesting places since they came to China.

  A.will visit   B.has visited   C.have visited   D.visited

4.Except for some twins,every living thing has its own unique DNA.

　◆except for意为“除……之外,要不是由于”,它要求排除的是不同类的。

　【辨析】except for,except,besides,but

　(1)except for意为“除了”,表示对主体的肯定和局部的否定,用于不同类的事物间，可以用在句首。

　(2)except可用作介词,意为“除了……之外”,后面可接名词、代词、动词、副词、介词短语或从句等,表示同类事物间的排除关系,一般不用于句首。

　(3)besides可用作介词,意为“除……之外”,表示同类事物间的叠加关系。

　(4)but可用作介词,意为“除……之外”,常与no,all,every,each,none,nobody等词连用,有时可与except互换。

用except，except for，besides填空

  1) We have an English lesson every day __________ Sunday.

 2) I sold everything ___________ my car and my books.

 3) We all went to the zoo __________ Li Ming.

 4) Smith is a good man，___________his bad temper.

三、知识点拨：

1.in general意为“一般而言,概括说来”,通常置于句首,也可以用generally speaking来表示。

2.different为形容词,意为“不同的”,常用于以下结构中:be different from与……不同;be different in...在……上不同。

3.比较级前可以用much,even,still,far,a bit,a little,a lot等词加以修饰。

4.(1)except for“除……以外,只是”,排除的不是同类,表示对主要部分的肯定和对局部的否定。

如:Your article is quite good except for several spelling mistakes.

你的文章很好,只是有几处拼写错误。

(2)except“除……之外”,排除后面的人或物,而且排除的内容和主语往往是同一类。

如:We all went to see our teacher yesterday except Li Ming.

昨天除了李明以外我们都去看我们的老师了。(李明没去)

(3)besides“除……之外(还)”,包括该词后面的人或物。

如:We all went to see a film besides Li Ming.

除李明以外我们也都去看电影了。(李明去了)

5.health为不可数名词,意为“健康”,常构成短语in good/bad health,意为“健康/不健康”。

【拓展】(1)healthy为形容词,意为“健康的”,unhealthy意为“不健康的”;keep/stay healthy意为“保持健康”。

(2)healthily为副词,意为“健康地”,eat healthily意为“吃得健康”。

6.not only...but also...“不但……而且……”连接两个相同的成分,也可连接两个分句。连接两个并列主语时,谓语动词和临近主语保持一致;连列两个并列分句时,not only置于句首,通常用倒装结构,也就是说,把not only引导的分句中的助动词或be动词提到主语前面。

7.be related to意为“和……有联系,和……有关,与……有亲属关系”。relate为动词,意为“把……联系起来”,常与to搭配。

8.one of the most amazing things意为“最令人惊奇的事情之一”,为“one of the+形容词的最高级+复数名词”结构。其中定冠词the也可使用形容词性物主代词来代替。

四、【知识巩固】

Ⅰ.用括号内所给单词的适当形式填空

1.This is the 　　　(identify) hotel that we stayed in last year. 

2.Your brothers are people 　　　(relate) to you. 

3.Do you know who is the 　　　(own) of the house? 

4.Your body uses this pattern 　　　(build) itself. 

5.You have your own DNA,but it repeats the patterns from your 　　　(parent) DNA. 

6.Some health problems come from your family’s DNA.　　　(science) can look for these problems in your DNA. 

Ⅱ.同义句转换

1.Both you and Linda give us a big surprise.

　　　 　　　 you 　　　 　　　 Linda 　　　 us a big surprise. 

2.It takes me half an hour to clean up my room.

I 　　　 half an hour 　　　 up my room. 

3.My book isn’t the same as his.

My book is 　　　 　　　 his. 

4.What do you do with this problem?

　　　 do you 　　　 with this problem? 

5.He can speak Chinese.

He is 　　　 　　　 speak Chinese. 

6.I don’t know how I can build a house.

I don’t know how 　　　 　　　 a house. 

答案：

一、课前预习

核心单词　1.general　2.repeat　3.grandson

4．granddaughter　5.instruction　6.蓝图　7.复杂的

8．双胞胎之一；孪生儿之一　9.模式；形式　10.确认；鉴别　

11．有关的；相关的

单词变形　form

二、Step 1.自主探究，合作交流：

1. A blueprint is a drawing that shows how to put a house together with many different parts.

2. Building a living thing.

3. Yes, they do.

4. Yes. In the future, scientists might be able to

change our DNA.

5. People who are related to me. For example, my parents and grandparents.

Step 2. 交流展示

1. 可数名词；copies；及物动词；名词或代词；  1) copying   2) copies

2. much, even；   1) D      2)far more interesting

3. but also后面的主语;      C

4. 1) except  2) but  3) besides  4) except for

四、【知识巩固】

Ⅰ.1.identical　2.related　3.owner　4.to build　5.parents’　6.Scientists

Ⅱ.1.Not only;but also;gives　2.spend;cleaning　3.different from

4.How;deal　5.able to　6.to build