人教版（2019）选择性必修 第三册Unit 2 Healthy Lifestyle Learning about language 课件（共15张）.pptxVIP

Period2LearningaboutlanguageTheinfinitiveoftheverbusedasthesubjectUnit2HealthyLifestyle

1.EnabletheStudentstomastertheusageoftheinfinitiveoftheverbasthesubject2.EnabletheStudentstousetherelevantgrammarflexiblyandauthenticallyintherealsituation.LearningAims.

TheInfinitive(todo…)

Lead-inLookatthefollowingsentencesandpayattentiontotheitalicizedinfinitives.Findmoreinfinitivesinthereadingpassage,andtelltheirmeaningsandfunctions.1.Tochangebadhabitsisnevereasy.2.Ittookthesurgeonthreehourstofinishmymother’slungsurgery.3.TojointhePeople’sLiberationArmy,itisrequiredformentoshaveofftheirbeards.4.Itwasnotpolitetodisturbyourneighborswithloudmusiclastnight.5.(2023·全国甲卷)So,it’sbeenusefultoknowhowtocoverupholesandrepaintaroomtoavoidanychargeswhenI’vemovedout.

Moreinfinitivesinthereadingpassage1.…itcanbeeasyforsomeofthemtoformbadhabits.2.Afterall,itisnoteasytobreakbadhabits.动词不定式在句中做主语，有时为了保持句子的平衡，避免头重脚轻，常用it做形式主语，而真正的主语放在句子的末尾。比如第2，3，4，5例句。Theirmeaningsandfunctions

不定式的时态和语态：不定式主动被动?

一般towritetobewritten?

进行tobewriting?

完成tohavewrittentohavebeenwritten?

完成进行tohavebeenwriting?

1._________(talk)withhimisagreatpleasure.2.__________(help)othersisourduty.TotalkTohelpItisourdutytohelpothers.不定式作主语：it作为形式主语。

不定式作主语和动词-ing形式作主语和动词的区别：动词-ing形式和不定式作主语,都是说明一个内容。不定式通常表示一个将来的、具体的内容;但是,而动词-ing形式则表示一种经常性的、习惯的或抽象的概念。Tolookafterchildrenisherjobtoday.她今天的工作是看孩子。Lookingafterchildrenisherwork.她的工作是照顾孩子。

不定式作主语，it做形式主语的常见结构：Itis+adj.+(forsb.)todo(2024·浙江1月高考)Itissoeasytoletanonlinecourseslide,butyourgradeswillsufferasaresult.让在线课程进行下去是很容易的，但你的成绩会因此受到影响。(2022·全国乙卷)Itisalsohelpfulforyou