1、小議情態動詞Must 和Have to 的用法區別Must 和Have to二者均有“必須”的意思，其后均用動詞原形形式。但是二者用法又有明顯不同，下面將做詳細說明：A:關于Must 的用法：1、Must 用來表示必須時，強調的是主觀需要，發自自身內心的概念。2、Must 作為情態動詞而言，沒有人稱、單復數和動詞時態的變化。3、含有情態動詞must的肯定句變為一般疑問句時，需要將must提前到句首，注意第一人稱和第二人稱的轉換形式即可。對于一般疑問句的回答，其肯定回答要用Yes,主語+must。而對于其否定回答則不能用mustnt，因為mustnt表示不準、不應該，是一個表示命令性的禁止語氣的

2、單詞，而此處的語氣是一種勸告、勸說的語氣，所以只能用neednt或者是donthave to 進行回答。如：Must I finish homework this afternoon?Yes, you must.No, you neednt. or: you dont have to .4、含有情態動詞must的句子要變為否定句只需要在must后面直接添加否定詞not 即可，變為mustnt，如We students mustnt play soccer in the street .B:關于情態動詞have to 的用法：Have to 也表示必須，但強調的是客觀需要，有不得不、被逼無奈的做

3、某事。此詞既有人稱、單復數的變化、也有動詞時態的變化。同時其否定形式和其疑問句形式均需要借助助動詞do才可以進行變化。如：We have to stay in the classroom because we didnt finishour homework.She has to look after her mother at home.Does he have to go to bed now?Yes, he does./ /No, he doesnt .We dont have to clean the clean today.I will have to finish reading

4、the novel because my deskmate wants to get it this afternoon. C: must 還有表示“肯定性”猜測的語氣，意思是“一定，肯定”的概念。 如：This book must be Toms because his name is on the cover of the book .The teacher must be in the office .The light is on now.She must have a camera because I often see her take photos.此時一定要注意表示“可能性”猜測語氣（may）和“不可能性”猜測語氣（cant）的用法。May: She may be our English Teacher.Cant: The man you saw in the street cant be Mr Smith . He has alre