have-to的用法.txt.docx

have to 用法分析have to是情态动词，意思是“必须；不得不”，表示客观要做的事情，后接动词原形。一、have to的单数和复数have to虽是情态动词，但有人称或数的变化。一般现在时第三人称单数用has to，其他人称用have to。例如：You have to go with Tom你得跟汤姆去。She has to answer this question. 她不得不回答这个问题。二、have to的肯定式have to的肯定式由“have to+动词原形”构成。例如：I have to tell him the news.我得告诉他这个消息。She has to walk home她不得不走回家。三、have to的否定式have to的否定式由“dont have to+动词原形”或“doesnt have to+动词原形”构成。例如：You dont have to do like this.你不必这样做。He doesnt have to be there on time. 他不必按时到那里。have to的否定式还可在havehas后面加not （仅限于一般现在时和一般过去时）。例如：He hasnt to go there.他不必去那里。I havent to get up early.我不必早起床。四、have to的疑问式have to的一般疑问式通常由“Do/ Does + 主语+have to+动词原形+其他成分”构成，肯定回答用do或does；否定回答用dont（have to）或doesnt（have to）。例如：Do you have to go now?你现在就得去吗？Yes, I do.是的。Does he have to stay home? 他必须留在家里吗？Yes, he does. 是的。（No, he doesnt (have to) . 不，他不必留在家里。五、have to的时态have to可用于各种时态。其一般过去时的肯定式是had to，否定式是didnt have to；一般将来时的肯定式是will have to，否定式是wont have to。例如：He said he had to see me about something important他说他有重要的事情不得不见我。He said they didnt have to borrow 200 yuan from John他说他们不必向约翰借二百元。You will have to do that again你得重做那件事。She wont have to go with you. 她不必跟你去。六、have to与 must的区别1. have to有人称和数的变化，即第三人称单数用has to，其他人称用have to；而must没有人称或数的变化。例如：He has to go there他必须去那里。She must be off now她现在必须走了。2. have to有时态的变化，must没有。例如：He told me that I must be at the station by ten他告诉我必须十点前到达车站。He had to pay for it他不得不赔偿。3. have to强调客观上“不得不”做某事；must指主观上“必须”做某事。例如：We must study hard我们一定要努力学习。He had t