精品基础教育教学资料，请参考使用，祝你取得好成绩！Unit 13 We’re trying to save the earth【学习目标】(一) 知识与技能1. To learn different forms of verb.2. To understand the use of Modal Verbs.(二) 过程和方法3. To know how to use different forms of verb in different situations.4. To know how to use Modal Verbs in different situations.(三) 情感态度和价值观5. After learning this part, every student will be able to describe theirawareness of the serious situation of pullution and solutions to environmental problems using what we have learned in this lesson.【自主梳理】1. 判断下列句子中使用了什么时态及情态动词。

1. We are trying to save the earth.2. The river used to be so clean.3. It was considered the nicest river in the town.4. The air has become really polluted.\5. We should help savew the sharks.2. presentation1) verb forms2) Modal verbs.Main function of Modal Verbs.①. can (could) 表示能力，could主要指过去时间；表示允许。

②. may表允许，might可以指过去时间，也可指现在时间，语气更委婉。

③. must表示义务。

意为“必须”（主观意志）④. shall表征询意见⑤. will表意愿，用于各种人称陈述句；表请求，用于疑问句。

⑥. should / ought to应该【重点领悟】1) Fill in blanks with the correct forms of verbs.Interviewer: ___________ you ever ________ (take ) part in an environmental project?Ken: Yes, I have. I ___________ (help ) with a Clean-Up Day last year. It was _________ (consider) the biggest clean-up project this city __________ever ___________ (have).Interviewer: How many people __________ (take ) part?Ken: I ________ ( think) more than 1,000 people ________ (come) to help out. Interviewer: That’s fantastic! I guess everyone in this city is ____________ (try) to improve the environment.Ken: Yes, evertone should _____________(play ) a part in keeping the city clean.Possible answers: Have taken, helped, considered, had had, took, think, came, trying., play2) Fill in blanks with proper modal verbs.Can would could have to should might/may mustWhen it comes to saving the earth, people _______ think that big things __________be done. However, many forget that saving the earth begins with small things. For example, You _________ save electricity by turning off the lights when you leave a room. You ____ also use paper or reusable bags instead of plastic bags. In some stores, you now __________ pay for plastic bags. I think this is a great idea. And instead of driving to school or work, you ________ ride your bike or walk. If it’s far, you ________ take the bus. All these small things ______ add up and【探究提升】一．Fill in blanks using proper forms of given words.1、I'll give the book to him as soon as he _______ back(come).2、______ the baby _______ crying yet? (stop)3、I don't know whether mother ________ me to beijing next month.(take)4、she ________ on her coat and went out. (put)5、“What are they doin g?”“They _______ ready for the sports meeting.” (get)6、The boy asked his mother ________ him go and play basketball.(let)7、I’m sorry to keep you ________ for a long time. (wait)8、It ______ (take) him half an hour ________ (finish) his homework yesterday.9、If it _______ an interesting film, we’ll see it tomorrow. (be)10、They usually _________ (do) their homework after supper.11、Listen! who __________ (sing) in the next room now?12、_______ (be) your parents in shanghai last year?13、Mr. yu ________ (teach) us maths since 1982.14、They will have a trip (旅行) to the great wall if it ________ (not rain) tomorrow.15、Li Ming often ________ (listen) to the radio in the morning. 二．Choose the best answers.1．-May I stop my car here?-No, you_＿＿＿.A. can'tB. mustn'tC. needn'tD. don't have to2. -Must we clean the house now?-No, you _______.A. needn'tB. may notC. mustn'tD. can't3. Man __die without water.A. willB. canC. needD. shall4. –You____ return the book now. You can keep it next week if you like.A. can'tB. mustn'tC. needn'tD. may not5. -Johnny, you____ play with the knife, you___ hurt yourself.A. won't...can'tB. mustn't...mayC. shouldn't, mustD. can't...shouldn'tAnswers:【自主梳理】1. 现在进行时2. used to3. 一般过去时的被动语态4. 现在完成时5. should【重点领悟】1) Have taken, helped, considered, had had, took, think, came, trying., play2) may, can’t, can, could, have to, may/might, should ,would, must【探究提升】1、comes2、has,stopped 3、will take4、put5、aregetting 6、to let7、waiting 8、took, tofinish 9、is10、do 11、is singing 12、were13、has taught 14、doesn'train 15、listensAAACB。