資源簡(jiǎn)介

(共48張PPT)
Unit 5
A delicate world
Part 1
Learning Objectives
Learning Objectives
Thinking quality: Lead students to learn and apply expressions related to food chains, understand the relationships among different species in various food chains in the ecosystem, guide students to recognize the importance of protecting the balance of food chains, and encourage students to contribute to the protection of the ecosystem.
Language ability:Guide students to further understand the importance of ecological balance through completing listening activities and be able to express their own viewpoints by applying what they have learned. At the same time, one can also pay attention to the pragmatic functions of the topic, learn to express doubts and respond to others' doubts.
Learning Objectives
Learning ability:Guide students to discover and understand the usage of "it" as a formal object through observation, and learn to apply it in real contexts.
Cultural awareness: Understand the significance of mutual restraint, interdependence, symbiosis and co-prosperity, as well as ecological balance among organisms in the food chain. Human beings can protect various ecosystems and promote ecological balance through their own efforts. Human beings can also do it for themselves plundering resources for immediate interests and disrupting ecological balance.
Part 2
Review
選擇題
1.In fact, ______ is a hard job for the police to keep order in an important football match.
A. this B. that C. there D. it
2.______ is a fact that English is being accepted as an international language.
A. There B. This C. That D. It
3.Is ______ necessary to complete the design before National Day
A. this B. that C. it D. he
4.______ will take you a lot of time to find him in the crowd.
A. It B. I C. We D. They
5.They are good friends. ______ is no wonder that they know each other so well.
A. This B. That C. There D. It
it 作形式主語
It as an empty subject—it 作形式主語
當(dāng)主語部分相對(duì)于謂語部分而言太長(zhǎng)時(shí)，常把主語部分移到句尾，在主語的位置放上it。
it 沒有具體的意義,僅用于使句子顯得平穩(wěn)，不頭重腳輕。
it 作形式主語時(shí)常代替三種語法結(jié)構(gòu)：不定式(短語)、v-ing(短語) 和從句。
1. it 代替不定式(短語)作形式主語
it 代替不定式(短語)作形式主語的常見句型:
It+be +形容詞 +(for/of sb.)to do sth
It + be + 名詞 + to do sth.
It takes sb.some time to do sth.
It's up to sb. to do sth.
It is difficult for a foreigner to learn Chinese. 外國人學(xué)習(xí)漢語不容易。
(It作形式主語，代替不定式復(fù)合結(jié)構(gòu)foraforeigner to leamn Chinese.)
It is everyone's duty to obey the law. 遵守法律是每個(gè)人的義務(wù)
(It作形式主語，代替不定式短語 to obey the law)
2. it 代替 v-ing (短語) 作形式主語
it 代替 v-ing(短語)作形式主語的情況遠(yuǎn)不及it 代替不定式（短語）作形式主語那么普遍。
常見句型：It+be+no good/no use/useless/a waste/+v-ing(短語)。
It is no good/use having a car if you can't drive.
如果你不會(huì)開車,有車也沒用。
(It作形式主語,代替v-ing短語having a car )
It is a waste of time watching TV.
看電視是浪費(fèi)時(shí)間。
(It作形式主語,代替 v-ing 短語 watching TV)
3. it 代替從句作形式主語
it所替代的從句可以用that引導(dǎo)，也可以用whether/if、連接代詞或連接副詞引導(dǎo)。
It was clear that they had no desire for peace.
顯然他們并不想要和平。
(It 作形式主語,代替從句 that they had no desire for peace)
It is doubtful whether she will be able to come.
她能否來還很難說。
(It作形式主語,代替從句whether she will be able to come )
4. it 作形式主語的常見句型
(1) It is a pity/a shame/a fact/an honour/good news/no wonder/a wonder/... that...
(2) It is+形容詞(strange /natural/surprising /obvious /true /fortunate /wonderful/funny/possible/impossible/likely/unlikely/clear/unusual/certain/important/...)+ that ...
(3) It happened/turned out/suddenly struck me/occurred to me/.../that...
(4) It +be+過去分詞(said /reported /announced /decided /expected /hoped /known /believed...) + that...
(5) It doesn't matter + that/what/where/whether/...
Part 3
While-class
Look at the sentences and answer the questions. Sentence (a) and Sentence (c) are from the reading passage.
a No visitor would think it surprising that the island is a UNESCO World Heritage Site.
b No visitor would think that the island being a UNESCO World Heritage Site is surprising.
c Experts felt it necessary to come up with a plan to remove all the rabbits from the island.
d Experts felt to come up with a plan to remove all the rabbits from the island was necessary.
1. What does “it” refer to in sentences (a) and (c)
“It” in sentence(a) refers to“the island is a UNESCO World Heritage Site”.
“It” in sentence (c) refers to “to come up with a planto remove all the rabbits from the island”.
a No visitor would think it surprising that the island is a UNESCO World Heritage Site.
b No visitor would think that the island being a UNESCO World Heritage Site is surprising.
c Experts felt it necessary to come up with a plan to remove all the rabbits from the island.
d Experts felt to come up with a plan to remove all the rabbits from the island was necessary.
2. What is the difference between the sentences in each group
When the object of a sentence is a that-clause(b) or an infinitive (d), we sometimes use “it” as an empty object and put the real object later to keep balance. For example,sentence(a)uses “it’ as the empty object of “think”, referring to the real object: “the island is a UNESCO World Heritage Site”. Sentence (b) uses that-clause as the object of “think”.
Grammer
It as an empty object—it 作形式賓語
當(dāng)動(dòng)詞不定式（短語）、v-ing(短語）或從句作賓語時(shí)，為了保持句子結(jié)構(gòu)的平衡，常用it作形式賓語，而將真正的賓語后置。此時(shí)的it無詞義。
Grammer
it 作形式賓語
（1）常以it作形式賓語的動(dòng)詞有：feel, consider, find, believe, make, take, imagine, prove, think, suppose, regard, notice等。
I find it easy to get on with Jim.
我發(fā)現(xiàn)同吉姆相處很容易。
（2）it 作形式賓語，代替動(dòng)詞不定式（短語）
They found it pleasant to work with us Chinese.
他們發(fā)現(xiàn)與我們中國人一起工作很愉快。
Grammer
it 作形式賓語
（3）it 作形式賓語，代替 v-ing(短語）
用 v-ing(短語）作真正的賓語時(shí)，其賓補(bǔ)通常是 no use, no good, a waste, hard work等。
I think it no good spending too much time watching TV.
我認(rèn)為花太多時(shí)間看電視是沒有好處的。
I feel it hard work persuading him into doing it.
我感覺說服他做那件事很難。
Grammer
it 作形式賓語
（4）it 作形式賓語，代替從句
①在一些習(xí)慣用法中, it在hate,like,love,appreciate,enjoy,take,have等動(dòng)詞后作形式賓語，代替其后的賓語從句。
I hate it when he talks with his mouth full.
我討厭他一邊吃一邊說話。
I like it when a book is so good that you cannot put it down.
我喜歡那種碰上好書時(shí)手不釋卷的感覺。
Grammer
it 作形式賓語
②在一些特殊結(jié)構(gòu)中，用it作形式賓語。
take it for granted that...認(rèn)為......是理所當(dāng)然
see to it that...確保......
owe it to...that... 多虧....../幸虧......
We all take it for granted that James will win the game.
我們都確信詹姆斯將贏得這場(chǎng)比賽。
Would you see to it that she gets home early
你保證她早早到家，好嗎？
It as an empty object and empty subject.
Rewrite the underlined parts using it as an empty object.
The red-eared slider, a species of freshwater turtle, is native to the Southern United States and Northern Mexico. Due to its cute appearance, many people think keeping this turtle as a pet is a good idea. Recent years have seen more and more pet sliders escaping or being released from homes, and some owners believe to release them into the wild is no big issue.
many people think it a good idea to keep this turtle as a pet
believe it no big issue to release them into the wild
Rewrite the underlined parts using it as an empty object.
These days, people have found to release these turtles into the wild is a threat to other species. Experts consider owners keeping their pets in an enclosed area important, and anyone unable to keep their pets should take them to an appropriate animal shelter.
people have found it a threat to other species to release these turtles into the wild
Experts consider it important for owners to keep
their pets in an enclosed area
Look at the pictures of the Saihanba National Forest Park and describe its changes using it as an empty object where appropriate. You may refer to the words and expressions in the table for help.
Look at the pictures of the Saihanba National Forest Park and describe its changes using it as an empty object where appropriate. You may refer to the words and expressions in the table for help.
nouns / adjectives to do / that
breakthrough impossible likely unrealistic ... grow
investigate
plant trees
transform
...
I think it a breakthrough to transform
a desert into a forest…
Sample
Saihanba National Forest Park stands as a shining example of ecological restoration. Decades ago, scientists investigated this area and found it nearly impossible to grow trees here due to harsh conditions. Many believed transforming it was unrealistic , with freezing temperatures and poor soil making planting trees extremely difficult.
However, through persistent efforts, foresters achieved a major breakthrough . They discovered it essential to select cold-resistant tree species. Slowly but surely, it became likely for vegetation to take root. Today, it amazes visitors to see how this former wasteland has become China's largest man-made forest. The park now covers 82% of the area with lush trees, proving it possible to restore even the most damaged ecosystems.
Saihanba's story teaches us that while nature's recovery may seem challenging, human determination can make it happen.
Producers absorb water and dissolved nutrients from the soil. They also make their own food by absorbing light from the sun.
Primary consumers rely on vegetation to provide energy. They feed on green plants.
Secondary consumers prey on primary consumers, as well as eating other animal matter.
Decomposers break down dead animal and vegetable matter into nutrients. The dissolved chemicals are then released back into the food chain, to be used by producers.
Look at the diagram and answer the questions. Pay attention to the words and expressions in bold.
1.What does the diagram show
2.What are the relationships between the living things
The diagram shows a food chain-the connection between the living things.
The living things are closely connected with each other by the food they eat. Secondary consumers prey on primary consumers,primary consumers feed on producers,and producers absorb light from the sun, and water and dissolved nutrients from the soil, which are provided by decomposers.
Complete the passage with the correct form of the words and expressions in Activity 5.
In a woodland ecosystem, trees and other plants are producers. They 1____________ water, and take in nutrients from the soil and energy from the sun. Insects are an example of a primary consumer. They 2____________ the producers to provide food for them, and are 3____________ by secondary consumers: small mammals and birds. They 4____________ the primary consumers. Fungi and bacteria are decomposers. They 5____________ animal waste and the remains of living things. The chemicals these decomposers 6____________ fertilise the soil and give the plants the nutrients they need to grow.
absorb
rely on
fed on
prey on
break down
release
Have you ever observed bees What do you think about bees
One of the oldest species in the ecosystem, the honey bee has been in existence for millions of years.
A honey bee can fly as fast as 24 kilometres per hour and its wings can beat 200 times per second.
In just one journey to collect pollen and nectar, one single honey bee can pollinate as many as 50 to 100 flowers.
Now talk about the importance of bees.
Listen to the conversation and choose the true statements.
1.Bees are very important to our food supply because they provide honey.
2.The bee population is declining.
3.Without bees, humans would die out.
4.All human crops depend on bees for pollination.
5.If bees became extinct, other insects could pollinate enough crops.
6.Humans are responsible for the decline in the bee population.
Listen to the conversation and choose the true statements.
A combination of things damages bee habitats, mainly 1　　　　　　　　　　　　　.
The bee population is 2　　　　　　　　　　. According to statistics, bee numbers in the US 3　　　　　　　　　　 in just one year.
Without bees, crops would 4　　　　　　　　　　. 5　　　　　　　would not be able to compensate for the loss of bees, because 6　　　　　　　　　　　　　　　　　　　　of the species of crops.
Animals that live on the crops 7　　　　　　　.
Humans have nothing to eat and die out.
pesticides and climate change
declining very quickly
have fallen by 17%
be unable to reproduce
Other insects
bees are responsible for pollinating about 70 %
would die out
Complete the boxes with the expressions from the conversation.
You must be kidding!
I don't believe it!
It's a fact!
Don't forget that...
Are you sure about...
Check it out for yourself
According to statistics...
Expressing doubt
Responding to doubt
You must be kidding!
I don't believe it!
Are you sure about...
It's a fact!
Don't forget that...
Check it out for yourself...
According to statistics...
Pair work
Talk about what would happen to the ecosystem if another species died out. Use the words and expressions in this section.
Every species plays a vital role in maintaining ecological balance. If one species goes extinct, it can trigger a chain reaction that disrupts the entire ecosystem.
First, the loss of a species may break food chains. For example, if bees disappear, it becomes difficult for plants to pollinate, affecting herbivores and eventually carnivores. Scientists warn that it could lead to biodiversity decline, making ecosystems more vulnerable to diseases and climate change.
Pair work
Talk about what would happen to the ecosystem if another species died out. Use the words and expressions in this section.
Moreover, it often causes unexpected consequences. Some species might overpopulate without natural predators, while others could starve. This imbalance makes it harder for ecosystems to recover.
Ultimately, protecting endangered species isn't just about saving animals— it ensures our planet's health. As the saying goes, "When one species suffers, it affects us all."
Part 4
After-class
Vocabulary
1. absorb
be/get absorbed in 全神貫注于
be absorbed into 被納入/并入
absorption n.吸收；并入；全神貫注
練習(xí)：
Catherine was seated in the sofa, totally _________ (absorb) in the book about youth and love.
absorbed
Vocabulary
2. issue
a key/sensitive/controversial issue 關(guān)鍵的/敏感的/有爭(zhēng)議的問題
issue a passport/visa 簽發(fā)護(hù)照/簽證
issue a magazine發(fā)行一本雜志
issue a set of stamps發(fā)行一套郵票
練習(xí)：
The police __________ (issue) an appeal for witnesses before the reporters came.
had issued
Vocabulary
3. appropriate
be appropriate to/for sth 對(duì)……適合
It is appropriate (for sb) to do sth (對(duì)于某人來說)做某事合適
appropriately adv.恰當(dāng)?shù)?br/>inappropriate adj.不合適的；不恰當(dāng)?shù)?br/>練習(xí)：
現(xiàn)在發(fā)表演講是不是時(shí)候？
________________________________________.
Is now an appropriate time to make a speech
Vocabulary
4. break down
break one's promise 食言
break away from 逃脫；掙脫
break in 強(qiáng)行進(jìn)人；打斷談話
break into 強(qiáng)行闖入；突然開始笑、唱等
break off 停頓；使折斷；突然終止
break out 爆發(fā)；突然發(fā)生
break through 突破；沖破；克服
break up 解散；（學(xué)校）放假；結(jié)束；破裂；粉碎壞回
練習(xí)：Don't break _____ when he is telling the story.
in
Part 5
Exercise
在空白處填人1個(gè)適當(dāng)?shù)膯卧~或括號(hào)內(nèi)單詞的正確形式。
1.The artist was absorbed　　　　　painting completely, losing track of time.
2.The old scientist decided to devote the rest of his life to scientific
　　　　　　　(investigate).
3.It may take hundreds of years for plastic to break 　　　　　, but much less time for paper.
4.The boy was curious about how the waste paper was transformed　　　　　a kite.
5.Such customs have been　　　　　existence for thousands of years in our country.
6.Only when we learn to exist in harmony with nature can we stop being a threat
　　　　　wildlife and our planet.
in
investigation
down
into
in
to
Exercise
1. No one found ____ strange that he should finish his huge pile of work in a single day.
2. He wants to make it fixed _____ the party is going to be held so that he can arrange his time for tomorrow.
3. Students feel it free ________ (choose) whatever class to take.
4. Mark found it excited that he _________ (go) to China as an exchange student next year.
it
when
to choose
would go
在空白處填人1個(gè)適當(dāng)?shù)膯卧~或括號(hào)內(nèi)單詞的正確形式。
Exercise
單項(xiàng)選擇
1．Experts felt ________ necessary to come up with a plan to remove all the rabbits from the island.
A．that B．this C．it D．one
2．We think possible that you can finish the essay today.
A．it B．that C．them D．if
3．Don’t take _______ for granted _______ everyone should adore you.
A．that; what B．it; that
C．it; what D．that; which
Exercise
單項(xiàng)選擇
4．We find _______ difficult to talk to him about anything serious.
A．him B．he C．ourselves D．it
5．We all thought ______ a question ________we could raise enough money for the project.
A．that; that B．it; whether C．it; that D．that; whether
6．I’d appreciate________if you would turn out the lights. I’m sleepy.
A．one B．that C．this D．it
7．No visitor would think _________ surprising that the island is a UNESCO World Heritage Site.
A．that B．it C．this D．what
Part 6
Homework
1.完成課后習(xí)題
2.以Describe how a place you know has changed using it as an empty object where appropriate.為話題，寫一篇作文
3.預(yù)習(xí)下節(jié)課文章
Homework
See you next class!

展開更多......

收起↑