資源簡介 (共28張PPT)Unit 5AdelicateworldUsing languageIT as an empty objectBY MICHELLEIt as an empty objectPart 01Look at the sentences and answer the questions. Sentences (a) and (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) 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”.Now look for more sentences with this structure in the reading passage, and summarise its use in your own words.This incident made it clear that the rat, mouse and rabbit problem needed solving once and for all.…but we humans owe it to the island to give it a happy ending.It作形式賓語條件真正的賓語是有賓語補足語不定式動名詞從句具備了這兩個條件, 形式賓語it一定要用。it 作形式賓語的常見情況歸納如下:1. it代替不定式短語。常用于:think/ find/ feel/ consider/ make/ regard... it + adj./n. + to doI find it pleasant to work with him.They felt it difficult to finish the work in such a short time.She thinks it her duty to help him.All these noises made it impossible for me to go on with the work.2. it代替v.-ing只限于少數(shù)句型。consider/think/find... it + good/ use/ worthwhile... + doing...The professor considers it no good reading without understanding.Do you consider it any use arguing with him I don’t think it worthwhile going to such a place.it 作形式賓語的常見情況歸納如下:3. it代替賓語從句(that有時候可以省略)。think/find/make... it + n./adj. + Object Clause...We all thought it a pity that the conference was cancelled.They kept it quiet that he was dead.He hasn’t make it clear when he is coming back.it 作形式賓語的常見情況歸納如下:it 作形式賓語還有幾種特殊情況,歸納如下:動詞+ it + that從句,常見于put, have, take等動詞后。I take it that he will finish the task by himself.動詞+ it + when/if從句,常見于appreciate, enjoy, like, prefer等動詞之后。We really appreciate it if you could do us a favour.We owe it to you that we are still alive.I took it for granted that they were not coming.動詞 + it +介詞短語 + that從句,常見于owe it to sb, take it for granted等結(jié)構(gòu)中。動詞+介詞+ it + that從句,常見于look to, depend on, insist on, stick to, answer for等結(jié)構(gòu)中。She insisted on it that she was innocent.You may depend on it that he will help you.He made it known to everyone that he was right.They haven’t made it known where they are to hold the conference.動詞+ it +過去分詞+從句。根據(jù)括號內(nèi)的漢語提示并用it作形式賓語補全下面句子。1. _______________________ (我認為那很重要) to find a part-time job.2. _______________________________ (新技術(shù)使之成為可能) to achieve a balance between economic development and ecosystems.3. _______________________ (他們覺得很困難) to recover the original ecosystem in such a short time last year.4. ______________________________________ (你為何不讓人們引起注意) that our actions, no matter how small they may be, make a difference to nature I consider it importantNew technologies make it possibleThey felt it very difficult Why don't you bring it to people's attentionRewrite the underlined parts using it as an empty object.many people think it a good idea to keep this turtle as a petbelieve it no big issue to release them into the wildpeople have found it a threat to other species to release these turtles into the wildExperts consider it important for owners to keep their pets in an enclosed areaLook at pictures of Saihanba National Forest Park and find out the changes./Located in Chengde City, Hebei Province, Saihanba (塞罕壩) sits 450 kilometers to the north of Beijing. The place is covered with snow seven months a year. It used to be a freezing, barren desert plagued by sandstorms. However, it has been turned into the world’s largest human-made forest that covers an area of nearly 75,000 hectares. Thus, it is called a “green miracle.”Background Informationnouns / adjectives to do / thatbreakthrough impossible likely unrealistic ... growinvestigateplant treestransform...Now describe its changes using it as an empty object where appropriate. You may refer to the words and expressions in the table for help.I think it a breakthrough to transform a desert into a forest...I think it impossible to grow trees there in the 1960s.I think it unrealistic to plant trees in the desert when the workers first came to Saihanba.EcosystemsPart 02Look at the diagram and answer the questions. Pay attention to the words and expressions in bold.What does the diagram show What are the relationships between the living things What does the diagram show 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. Worms, 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 absorb dissolve nutrients rely on provide energy feed on prey on break down releaserely onfed onprey onbreak downreleaseOne 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.Did You Know 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 again and complete the flow chart.pesticides and climate changedeclining very quicklyhave fallen by 17%be unable to reproduceOther insectsbees are responsible for pollinating about 70%would die outNow talk about the importance of bees.Complete the boxes with the expressions from the conversation.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…Work in pairs. Talk about what would happen to the ecosystem if another species died out. Use the words and expressions in this section.Review it as an empty object.Describe how a place you know has changed using it as an empty object where appropriate.THANKS FOR WATCHING 展開更多...... 收起↑ 資源預(yù)覽 縮略圖、資源來源于二一教育資源庫