12Unit3Languageinuse祈使句结构如下：(Please)+dosth.(Please)+Don’tdosth.肯定：否定：DO，可以放在动词前，为加强语气用。如：Docomein,please!Dolistentome,please!Doopenthedoor,please!一、我们已经学习的表推测的情态动词有：must/can/could/may/might二、表推测的三种句式：1.在肯定句中一般用must，can/could，may/might，程度逐渐减弱。e.g.Hemust/may/mightknowtheanswertothisquestion.e.g.Youhaveworkedallthisweek.Youmustbetired.2.在否定句中用can’t/couldn’t(不可能)，maynot/mightnot(可能不)。e.g.Itcan’t/couldn’tbetheheadmaster.HehasgonetoAmerica.e.g.Hemaynot/mightnotknowthescientist.3.在疑问句中，一般只使用can/could。e.g.Couldhehavefinishedthetask?e.g.Canhebeathomenow?LanguagepracticeThatcouldbeharmful!Betty,youmustknow!Stayawayfromwindowsandheavyfurniture.Donotstandnearstreetlightsorunderpowerlines.1.Itisdangerous.You________keepout!2.Thesestairsarenotsafe.You_______usethem.3.Therocksarefallingdown.You______gethit.4.Theriveristoodeep.You________swiminit.5.Betty_______knowwhattodo,becauseshedidsomebasicmedicaltraining.1Completethesentenceswithcould,mustormustn’t.mustmustn'tcouldmustn'tmust2Underlinethecorrectwordstocompletethefirstaidinstructions.1Get/Donotgetmedicalhelpimmediately.2Ask/Donotaskthemwherethepainis.3Lift/Donotliftthembecauseyoumaydropthem.4Keep/Donotkeepthemwarm.3Completetheposteraboutearthquakewiththecorrectformofthewordsandexpressionsinthebox.donotusehideunderkeepleavestayaway1____________fromthewindows.2___________atable.3___________thelift.4__________thebuildingquicklywhenthegroundstopsshaking.5_________calm.Whenthereisanearthquake…StayawayHideunderDonotuseLeaveKeep4Completetheconversationwiththewordsandexpressionsinthebox.Tony:Damingistraininghardforthebigmatch.Lingling:Yes,theteamhasagood(1)________thisyear.Tony:Ohno,Daming’s(2)___________.He’sdown!Lingling:Itlookslikehe’s(3)__________Tony:Daming,whathappened?chanceCoverinpainintroublemedicalchanceintroubleinpainDaming:It’smyleg.Lingling:(4)_________himwithmycoat.Tony:Butdon’tmovehim.Let’swaitforsom...
