高二英语选修6 Unit3 教案5.doc

教案3Unit3Ahealthylife
Grammar

Teachingmaterial
NSEFCBook6——Unit3
Teachingaims
Enablethestudentstomastertheusageofit.
Teachingimportant&difficultpoints
Howtoenablethestudentstoknowtheusageofit.
Teachingaids
taperecorder,slides
Teachingprocedures
Step1Revision
Completethepassagewiththesuitablewordsintheirproperforms.
dueto6.stress
addicted7.quit
alcohol8.drugs
manage9.pregnant
cigarettes10.adolescents
Smoking__________,drinking_______ortakingother__________producemanyharmfuleffectsandhavenorealbenefits.Sowhydo___________doit?Somebeginbecausetheybelieveitmakesthemlookcool.Othersthinkitwillhelpwith_______.Intheirlifepossibly________pressurefromtheirparentsorteachers.
Somejustwanttoseewhatitislike.Whattheydon’trealizeisthattheywillgetintothehabitand__________become____________.Itwillthenbedifficultto_________thehabit.Afewpeople________toquiteasilybutformanyitisaverypainfulprocess.Ofcourse,thebestwaytodealwiththesedrugsisnottostartinthefirstplace.
Keys：cigarettes；alcohol；drugs；adolescents；stress；dueto；eventually；addicted;quit；manage
Step2Leadin
Slideshow
Discovering“It”
1．Itrainsheavily.指天气
2.Itis20kilometersfromGranddad’shousetoJames’.指距离
3.ItisNovember11,2005.指日期
4.Itis9o’clockatnight.指时间
5.Itisbadtosmoke.形式主语
6.Itisnogoodsmoking.形式主语
7.Itislikelythathewillsucceed.形式主语
Step3Theuseof“it”
一、“it”作人称代词
1.it的最基本用法是作代词，主要指刚提到的事物，以避免重复:
Xi’anisabeautifulcity,isn’tit?
Theywatchedthetrainuntilitdisappearedinthedistance.
2.也可以指动物或婴儿(未知性别的婴儿或孩子):
Isthisyourdog？No,itisn’t.
二、it作非人称代词
it有时并不指具体的东西，而泛指天气、时间、日期、距离、价值、度量、温度、环境等，称为非人称的it：
指天气：
Itisalovelyday,isn’tit?
Itisabitwindy.2.指时间:
Itwasnearlymidnightwhenshecameback.
3.指环境:
Itwasveryquietinthecafé.
4.指距离：
Itishalfanhour’swalktothecitycentrefrommyhome.
5.指日期：
What'sthedatetoday?It'sMay1,2007.
6.指季节：
Itissummernow.
7.指度量：
Itisabout5kilograms.
8.指价值：
----What'sthecostoftheT-shirt?
----Itis150Yuan.
三、it用作形式主语
替代作主语的从句、动词不定式、动名词，而把真正作主语的从句、动词不定式、动名词置于句尾。
1.代作主语的动词不定式，其句型为
（1）Itbeadj.（forsb.）todosth.
此处adj.通常为描述事件的形容词：easy，diffi