Unit 5 Lesson 28The Study of Living Things课件(共27张PPT) 冀教版九年级全一册

(共27张PPT)
Unit 5
Look into Science
Lesson 28
The new words:
Chip Taylor, biology, butterfly, migrate, fantastic, completely, grandchild, female, milkweed, chemical, puzzling
Important and difficult points:
1) Fantastic facts about the butterfly have been drawing Dr. Taylor’s attention.
2) Here, as many as 230 million butterflies spend the winter.
3) But in Mexico, people cut down the trees that the butterflies need to rest on because they want more land for farming.
4) This is both puzzling and interesting for many scientists.
学习目标
1
2
Do you like nature Why
Lead in
Would you like to be a biologist when you grow up Why or why not
What mysteries of nature do you know about
Ask and answer
新课讲授
Listen and imitate
Dr. Chip Taylor teaches biology at a university in the United States. He studies one kind of North American butterfly. Just like a migrating bird，this butterfly travels about 4 000 kilometres south in fall. Fantastic facts about the butterfly have been drawing Dr. Taylor′s attention.
Butterflies are beautiful. What do you know about them
In Mexico，the butterflies always return to the same small piece of forest，which is only 20 kilometres wide. Here, as many as 230 million butterflies spend the winter. They can cover some trees almost completely. The butterflies that return to the south are the great great grandchildren of the butterflies that left for the north. When they begin to travel north in spring，the females lay eggs. They lay eggs on only one plant ： milkweed.
But in Mexico，people cut down the trees that the butterflies need to rest on because they want more land for farming. In the United States and Canada，farmers use chemicals that kill milkweed. This worries Dr. Taylor a lot.
Now things are improving. Mexico has begun to protect parts of its forests. The United States and Canada have encouraged farmers to use less chemicals.
Scientists still don′t understand how the butterflies know when to fly south. If they are even a few days late，they will freeze. And how do all the great great grandchildren find the same forest in Mexico every year This is both puzzling and interesting for many scientists.
There are many mysteries yet to be discovered by those interested in science. Would you like to study biology
1. Fantastic facts about the butterfly have been drawing Dr. Taylor’s attention. 这些有关蝴蝶的奇异的事实引起了泰勒先生的注意。
fantastic作形容词，意为“奇异的、极好的、了不起的”，在句中作定语或表语。
e.g. ① I think this is a fantastic invention.
我想这是一个了不起的发明。
② These flowers are so fantastic. They have many different colours.
这种花太奇异了。它们有很多不同的颜色。
Language points
draw one’s attention 引起某人的注意
句中的have been drawing 是现在完成进行时，它由“助动词 have (has) + been + 现在分词”构成，当主语是第三人称单数时用助动词has，其他情况用助动词have。现在完成进行时主要表示从过去开始一直持续到现在的动作，这个动作是否延续下去，要根据上下文而定。它往往与表示一段时间的时间状语连用，如：all the time, this month, all day, these few days, for a year, since a week ago等。
e.g. ① She has been playing basketball after school this week.
这个星期她放学后一直打篮球。
② Tony has been drawing in his bedroom all the afternoon.
托尼在卧室画了一下午。
almost/' lm st/ adv.几乎，差不多
辨析 almost与nearly
almost和nearly这两个词都表示“几乎”，“差不多”的意思，在不少场合可以互换使用，但有以下区别：
2. They can cover some trees almost completely.
相同点 不同点
nearly 意思相近，肯定句中可以换用。 nearly可以和not连用，not nearly是“远不”的意思，但almost不和not单独连用。
The money will not be nearly enough for my journey. 这些钱远不够我旅行用。
almost almost能和never，no，none，nothing，nobody等词连用，这种情况下不能用nearly。
用almost或nearly的适当形式填空。
1．There was ________ no snow that winter.
2．We are ________________ there.
3．The speaker said ________ nothing that was worth listening to.
4．________________ all the students left here a few minutes ago.
almost
nearly/almost
almost　
Almost/Nearly
cut down 砍倒，缩减
e.g. They cut down the big tree.
他们把这棵大树砍倒了。
You’d better cut the article down to about 500 words.
你最好把这篇文章压缩到五百字左右。
3. But in Mexico，people cut down the trees that the butterflies need to rest on because they want more land for farming.
与cut有关的短语有：
cut in 打断(谈话)，插嘴
e.g. Don’t cut in when others are talking. 当别人正在讲话时不要插嘴。
I was just coming to that point when you cut in.
我刚要谈那一点，你就打断我了。
cut off 切断，断绝
e.g. The flood cut the villagers off from the rest of the world.
洪水切断了村民与外界的联系。
cut out 删除，停止做(或使用、食用)
e.g. I’ve been advised to cut sugar out of my diet. 有人劝我饮食要忌糖。
I cut out one paragraph in this article. 我删除了这篇文章的一个段落。
chemical作可数名词，意为“化学物质、化学制品”，
复数形式是chemicals。
e.g. There are no chemicals in this kind of food.
这种食品中没有化学物质。
chemical作形容词，意为“化学的、化学作用的”，在句中作表语或定语。
e.g. We can find chemical additives in many foods.
我们在很多食品中发现了化学添加剂。
4. In the United States and Canada, farmers use chemicals that kill milkweed.
worry /'w ri/ n.烦恼，忧虑v.担心，担忧
e.g. Don’t worry. I know how it turned out.
不要担心。我知道事情怎样发展。
worry作及物动词，构成结构：worry sb. 使某人担心。
e.g. I didn’t want to worry my friend.
我不想使我的朋友担心。
5. This worries Dr. Taylor a lot.
worry作不及物动词，常构成：
Don’t worry. 不要担心
worry about sth./sb. 担心某事/某人
e.g. Don’t worry. He’ll be all right. 别担心。他会平安无事的。
The child has nothing to worry about. 这个孩子没有什么可担心的。
worried adj. 担心的
be worried about sb./sth. 担心某人/某事
e.g. Don’t be worried about me. I can look after myself.
不用担心我。我能照顾自己。
6. This is both puzzling and interesting for many scientists.
对很多科学家来说这既令人费解又很有趣。
连词both…and…的意思是“……和……都，既……也……” 它可以连接句中句子成分相同的词语，如果用它连接主语时，谓语动词要用复数形式。
e.g. ①She likes both sports and music. 她既喜欢运动，又喜欢音乐。
②Both Li Ping and her mother take exercise every morning.
李萍和她妈妈每天早晨都进行锻炼。
1. Read the lesson and complete the table.
Fantastic facts about butterflies ·The butterflies always ________ to the same small piece of forest and ________ the winter there.
·The butterflies that return to the south are the great great grandchildren of the butterflies that left for the north.
·The females ________ eggs on only one plant: milkweed.
return
spend
lay
Let’s Do It!
find
Things that Dr. Taylor worries about ·In Mexico，people cut down the trees that the butterflies need to ______on.
·In the U．S.and Canada，farmers use chemicals that ______ milkweed.
Things that scientists can’t understand ·How do the butterflies know when to fly south？
·How do the great great grandchildren of the butterflies ________ the same forest？
rest
kill
2. Join the sentences to make attributive clauses.
Example：
We did some experiments yesterday. The experiments were fantastic.
The experiments that we did yesterday were fantastic.
1) I asked him to mail the letter. I wrote the letter to my cousin.
___________________________________________________
2) Yesterday I met a boy. The boy is a new member in our art club.
___________________________________________________
3) Mary was carrying a bag. The bag cost her a lot of money.
___________________________________________________
4) Football is a team sport. Football is popular all over the world.
___________________________________________________
I asked him to mail the letter that I wrote to my cousin.
Yesterday I met a boy who is a new member in our art club.
Mary was carrying a bag which cost her a lot of money.
Football which is popular all over the world is a team sport.
3. Work in groups of three to play a game.
Task tips：Each group should prepare some pieces of paper and divide them into three columns. Student A writes a person’s name in the first column，folds the paper and passes it to Student B．Student B writes a statement beginning with “who”，folds the paper and passes it to Student C．Student C must finish the sentence and read it out loud.
Example：
Mr. Brown who is a biologist will give us a talk…
一、根据句意及汉语提示完成单词
1．Do you like ________ (生物学) at school
2．Look! There are many___________ (蝴蝶) among the flowers.
3．This is a ________ (极好的) film.
4．I ___________ (完全地) forgot about it.
5．Many people ________ (迁移) to Canada in the 1800s.
biology
butterflies
fantastic
completely
migrated
当堂检测
二、单项选择
1．Our teacher often encourages him ________ hard.
　　A．work B．working
C．to work D．works
2．Since environment is too important to all of us, we human
beings had better ________ fewer trees.
A．turned down B．cut down
C．put down D．cut up
C
B
3．Look! My dog is ________ on the ground in the sun.
A．lie B．lay
C．laid D．lying
4．The photo ________ taken by my brother
last week is very nice.
A．which were B．that is
C．that were D. which was
5．The volunteer spoke as________ as she could to make
the visitors understand her.
A．clearly B．more clearly
C．most clearly D．the most clearly
D
D
A
三、用方框中所给单词或短语的正确形式填空
draw one’s attention, cut down, return to, female, puzzling
1．If you ____________the trees，you will harm the environment here.
2．The interesting story ________________.We all liked it.
3．The fact of this thing is ________ for scientists.
4．They ____________their own country.
5．The ________ butterflies lay eggs in spring.
drew our attention
cut down
returned to
female
puzzling
课堂总结
Words:
fantastic, almost, chemical, worry
Phrases:
draw ones attention, cut down, both...and...
Sentences:
1) Fantastic facts about the butterfly have been drawing Dr. Taylor’s attention.
2) Here, as many as 230 million butterflies spend the winter.
3) But in Mexico, people cut down the trees that the butterflies need to rest on because they want more land for farming.
4) This is both puzzling and interesting for many scientists.
1.Write a passage about your favourite writer.
2.Preview Unit 5-Lesson 29.
Homework