1.不同种类的污染2.河底3.把垃圾扔到河里4.在……中起作用differentkindsofpollutionthebottleoftheriverthrowrubbishintotheriverplayapartinI.Checkifyouknowthesephrases.5.在中国南部6.对……有害7.在……顶部8.海洋生态系统insouthernChinabeharmfultoatthetopoftheocean’secosystemPayattentiontothesentences.1.We’retryingtosavetheearth.2.Theriverusedtobesoclean.3.Theairisbadlypolluted.4.Noscientificstudieshaveshownthatsharkfinsaregoodforhealth.5.Weshouldhelpsavethesharks.PresentprogressiveusedtoPassivevoicePresentperfectModalverbs现在进行时:PresentProgressive结构:be(am/is/are)+v.-ing标志词：Look,Listen,now,rightnow…e.g.Look!Theboyiscrying.定义：表示说话时(瞬间)正在进行的动作,也表示目前或现阶段正在进行的动作。usedtodosth.表示过去常常做某事,而现在往往不做了,后接动词原形。beusedtodoingsth.表示习惯于做某事e.g.Iusedtogetupatsixo’clock.Joeisusedtodrinkingacupofcoffeeeverymorning.usedtodo与beusedtodoing被动语态：Passivevoice定义：表示主语是动作的承受者，即行为动作的对象的一种语态。结构：be+过去分词e.g.Anewschoolwasbuiltlastyear.Ourclassroomiscleanedeveryday.结构:has/have+过去分词标志词：already,yet,ever,never,since,for…e.g.Ihaven’tfinishedmyhomeworkyet.定义：表示动作已经完成,但对现在造成影响;或者表示从过去某一时间开始一直延续到现在并还可能持续下去的动作。现在完成时:PresentPerfectCompletethefollowingsentences.1.I_________(be)inBeijingfortwoyears.2.I_____never_____(hear)ofthatmanbefore.3.Tom__________(work)theresincetwoyearsago.havebeenhaveheardhasworked4.Thetwins___________(wash)theclothesforanhour.5.He_________(play)basketballsincethreeyearsago.6.Howlong____Sally_____(sing)yet?havewashedhasplayedhassung1.情态动词本身有一定的词义,表示说话人的情绪、态度或语气,但不能单独作谓语,只能与其他动词构成谓语。常见的有:can(could),may(might),must,need,shall(should),will(would)等。情态动词2.情态动词无人称和数的变化,后接动词原形。否定式是在情态动词后面加not。个别情态动词有过去式形式,可用来表达更加客气、委婉的语气。e.g.Kencanclimbupthetresslikeakoala.Tracycouldrideabicyclewhenshewasfiveyearsold.Youmustn’tplaywithfire.Itisdangerous.4aFillintheblankswiththecorrectformsoftheverbsinbrackets.Joe:_____youever______(take)partinanenvironmentalproject?Eric:Yes,Ihave.I______(help)withaClean-UpDaylastyear.Itwas__________(consider)thebiggestclean-upprojectthiscity____ever____(have).Havetakenhelpedconsideredhadhad参加Joe:Howmanypeople____(take)part?Eric:I_____(think)morethan1,000people______(come)tohelpout.Joe:That’sfantastic!Iguesseveryoneinthiscityis______(try)toimprovetheenvironment.Eric:Yes,wecan’taffordto____(wait)anylongertotakeaction!tookthinkcametryingwaitv.承担得起(后果);买得起4bFillintheblankswiththeappropriatemodalverbsfromthebox.People__________thinkthatbigthings______bedonetosavetheearth.Manyforgetthatsavingtheearthbeginswithsmallthings.Forexample,you____savemay/mightmustcancanwouldcouldhavetoshouldmustmay/mightelectricitybyturningoffthelightswhenyouleavearoom.You______alsousereusablebagsinsteadofplasticbags.Ithinkit’sagreatideathatyounow______payforplasticbagsinsomestores.Andinsteadofdrivingtoschoolorwork,you__________rideyourbikeorwalk.Ifit’sfar,you__________takethebus.Allthesecouldhavetocan/shouldcan/could关掉adj.可重复使用的付费;付出代价smallthings______addupandbecomebigthingsthat_________improvetheenvironment.Let’stakeactionnow!couldwould/can采取行动turnaround转身turnup调高(音量)turndown调低;拒绝turninto变成;进入turnon打开,发动turnoff关掉,关闭turnouttobe结果是turnover移交拓展:turn相关短语
