八年级英语下册Chapter2PollutionFighters课件牛津上海版.ppt

Chapter Two Pollution Fighters Look and ThinkWhat good are trees?We get shade from trees. We get__________from trees.better citiesWe get _____________from trees.wooden housesWe get __________from trees.furnitureWe get _____from trees.paperWe get _______from trees.pencilsWe get _____from trees.cokeWe get __________from trees.coffee beansWe get ______from trees.fruitsWhat do you know about…?How long do they live?Match the items on theleft with the average ages on the right.•a mice i 70 years•b trees ii 150 years•c tortoises iii 40 years•d whales iv 4000 years•e people v 3 yearsWhat does the word mean?1 1.supposea. knowb. think it is truec.ask3. releasea. bring inb. take awayc. let out5. communicating witha. attackingb. sending message/ signals toc. joining2. purea.not mixed with other fortable4. runninga.travelingb.workingc.playing6. hardly anya.quite a lotb.almost nonec.a large number1. sip a. made by nature, not by man2. nature b. unpleasant3. oxygen c. drink in small amounts4. hectares d. a life-giving gas found in air5. warn e. something produced by chemistry6. a chemical f. areas of 10000 square meters7. nasty g. gay that something bad ordangerous or may happensDo you know the meaning?Find the factsTrees:Trees:1. live much longer than people;1. live much longer than people;2. produce rubber, wood, paper, nuts, beans and fruit;2. produce rubber, wood, paper, nuts, beans and fruit;3. take oxygen from the air;3. take oxygen from the air;4. heat the air;4. heat the air;5. are like air conditioners;5. are like air conditioners;6. cannot protect themselves against insects;6. cannot protect themselves against insects;7. can share food and water with one another;7. can share food and water with one another;8. are in danger, mainly from insects;8. are in danger, mainly from insects;TTTTFFFFreleasecoolcanpeople/humansAnswer the questions1. We get some useful things from trees, don’t we?Yes. Two examples are wood and rubber.2. Is it true that trees do two main things to the air? Yes. They cool it and clean it. 3. I’ve heard that one tree has the power of 15 air conditioners. Is that right? No. One trees has the power of five air conditioners.4. Scientists know a lot about trees, don’t they? No. they are only now beginning to understand them.5. Can trees really communicate with one another?Yes. For example, if insects attack a tree, it can warm its neighbors.6. And can they really protect themselves from insects?Yes. They can produce a chemical that makes their leaves taste nasty.Answer the questions7. Can trees help one another?Yes. For example. They can join their roots together under-ground and pass food and water around. 8. Is it true that, every year, there are fewer and fewer trees in the world?Yes. The reason is that people cut down millions of trees, but replace hardly any of them.ListeningListen and complete the notice below by putting one word in each space.Eight reasons for helping to plant trees:1 Trees make streets more ________.2 Trees make streets less _____.3 Trees make our air _____.4 Trees make our air _____.5 Trees make _____ to keep us alive and _______.6 Trees provide us with _____ things like _____ and _____.7 Trees help us to fight ________.8 Trees are in _____.beautifulnoisypurercooleroxygenhealthyusefulfruitpaperpollutiondangerWhat are they doing now? They are having a rest under the trees. They are planting trees. They are picking apples from the apple trees.They are cutting trees. DiscussionMake a dialogue according to the model:A: What can we do to fight pollution?B: Always put litter in litter bins, and stop using plastic bags for shopping.A: Anything else?B: Stop factories from producing unhealthy gases, plant more trees in the streets, and make classrooms less noisy.A: Which ways are more important and which ways are less important?B: I think that …..Model:Write a report on fighting pollution Our group thinks that the most important way to fight pollution is to _____. The second is to _____. The third is to _____. The fourth is to _____. The fifth is to _____. Everyone in our group agrees/Most people in our group agree to this arrangement.Writing:Homework: Write a short article about building a new sitting-out area near Write a short article about building a new sitting-out area near your home for your school newspaper.your home for your school newspaper. Near my home, there is a _______. Some workers finished it last week. I watched them from my flat. First, __________(workers/arrive/lorry). On the back of the lorry there _____(be/trees/brushes). The workers _____(dig/holes/ground). Second, they _____(plant/trees/holes). Next, they brought some large containers. They _____(put/earth/containers). Then they ____ ( plant / brushes / containers ).Next, they _____(pick up/all rubbish) and _____(sweep/area/neatly). After that, they _____(water/plants/hose). Then the area was finished. Now it looks_____.Homework:Think over how many kinds of pollutions wehave learned before and what they are. After class, try to find the pollution fighters of themand write a composition about them.。