1, 在表示一次性动作时,have to和 have got to 是能够互换的: I have (got) to be back by ten o’clock. 本人必需10点前返回来。 2, 但是,当表示习气性动作时,特别是当句中含有表示经常性的副词(如always, often, sometimes等)时,则应运用have to , 而不运用have got to: I don’t usually have to work on Sundays. 通常本人再星期天不用工作。 3, have to 与 have got to 的另一区别,就是后者不大用于过去时。 They didn’t have to worry about money. 他们那时不用为金钱而操心。 4, 最后一个区别,就是have to 前可加助动词或神态动词,或者用在停止体和完成体构造中,而have got to却不能: I shall have to help him as much as I can. 本人将不得不尽本人所能去协助他。 have got to 可以自身否定 have to 需借助助动词
have to 的否定句和疑问句的构成往往要借助于助动词do的适当形式或助动词will即have to, has to, had to和will have to的否定式分别为don't have to, doesn't have to, didn't have to和won't have to,疑问句是在句首加助动词do的相应形式,句中还原成have to或把will放到句首。就是这么规定的啊。