情态动词must的用法市公开课一等奖省赛课微课金奖课件.pptx

Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,一、,must,含义,1.,表示义务、意图或提议,:,必须,You must do your homework first.,I must get up early.,2.,表示推测,:,一定,必定,He must be at home.,The pen must be Jims,.,第1页,二、,must,使用方法：,1,、必定式：,must+V,原；,You,must,finish your homework.,2,、否定式：,must+not+V,原；,You,mustnt,smoke here.,must not,表示禁止,第2页,3,、疑问式：,Must+,主语,?,Must,I clean the room at once?,我必须马上打,扫房吗？,Yes,you,must,.,是，你必须马上清扫。,No,you,dont have to(=neednt),.,无须啦。,在回答,must,引发问句时，假如是否定回复，可用,dont have to,或,neednt,(,无须,),，,但不能用,mustn,t,第3页,三、,must,与,have to,区,别,1,、,must,强调主观上认为“必须”做某事,而,have to,强调客观上要求“不得不”做某事。,I,have to,look after my sister.For my mother,went out.,I,must,work hard.,客观需要,主观意愿,第4页,I,had to,clean my bedroom yesterday.,He,has to,work hard.,He,doesnt,have to,work hard.,-,Does,he,have to,work hard?,-Yes,he,does,./No,he,doesnt.,2,、在必定句中，,have to,随人称和时态不,同而改变。其否定式和疑问式 组成与行,为动词,have,相同，需使用助动词。,第5页,请用,must,或,have to,适当形式填空,1.We _ be polite to our teachers at school.,2.You _ go outside to play as it is,snowing heavily.,3.Must I get to the station before 5 p.m.?,Yes,you _./No,you _.,4.I got up late this morning,so I _ take a taxi,to school.,5.Does she _ stay at home?No,she doesnt.,mustnt,must,had to,have to,must,dont have to/neednt,第6页,