= instead of watering the gardenРР3 Grammar Рmust和have to都表示必要性,Рmust 表示主观认为有必要,有义务,没有时太和人称的变化,Рhave to 表示客观环境方面的需要,除了“必须”之外,还有“不得不”的意思,有时态和人称的变化。 РMust you go now? 你必须现在走吗?РYes,I have to leave at once. 是的,我不得不马上就走?РWe must take a taxi. 我们必须乘坐出租车。(我们觉得有必要乘坐)РWe have to take a taxi. 我们不得不乘坐出租车。(因为没有其他交通工具)РР用Must 提问,只能用needn’t 来表达否定回答,Рneedn’t还可以表达have to 的否定回答,needn’t ,don’t need to和don’t have to 都表示不必要,而mustn’t 表示绝对禁止,没有选择的余地。Р例:РYou must arrive on time. РYou don’t have/ need to arrive on time. РMust I arrive on time? Yes, you must./ No, you needn’t / No, you don’t have to.РРYou mustn’t smoke in the hospitalРРI have to tell him the truth. I don’t have to tell him the truth.РDo I have to tell him the truth? Yes, you do. / Yes you must.Р No, you don’t (have/ need to) / No, you needn’t