Lesson 8 Let’s save our planetWhen is World Earth Day?It’s on April 22nd.What can we do to make our mother earth more beautiful?keep the rivers clean plant more trees and flowers protect wild animals ride the bikeWe can more. drive the carWe should stop driving the car all the time.cloth bagsWe can use . plastic bagsWe should stop using too many .keep the rivers cleanWe can .pour dirty things into themWe should stop pouring dirty things into them.What can we do to make our mother earth more beautiful?We can plant more trees and grass. We should stop cutting down too much trees.We mustn’t waste any paper. We can write on both sides of it.We must save every drop of water. We should recycle.We should also protect animals.1. We should ______ every ______ of water and every piece of paper.2. Before you _______ your _______ away, you should pick out things you can ________ .3. We live on the _________ and this ________ is our only homeland. So we should do everything to ___________ it.4. We must not _______ any _________. When we finish our work on the computer, we should turn it off.savedropthrowlitterearthrecycleplanetprotectwasteenergySummarize:情态动词的用法： must, can, could, may, might, shall, should, will 不受人称变化的影响，在情态动词后面加动词原形。What can we do to protect the environment?We shouldn’t throw litter on the ground.We should turn off the lights when we go out of the room.May I speak to ….., please?We must practice a lot. 1. We should stop _____ down too many trees. A. cut B. cutting C. cuts2. We should ______ wild animals. A. protect B. protecting C. protects3. We ______ waste any water, paper and energy. A. must B. needn’t C. mustn’t4. His English is ______ than the others in our class. A. good B. gooder C. better5. He isn’t at school today. He ____ be ill. A. should B. must C. will6. We shouldn’t pour dirty things ____ the river. A. in B. to C. into
