在表示一次性动作时,have to和have got to是可以互换的,如：
I have (got) to be back by ten o'clock.我必须10点前返回来.
I haven't got to work tomorrow.我明天不必上班.
但是,当表示习惯性动作时,尤其是当句中含有表示经常性的副词 （如always,often,sometimes等）时,则应使用have to,而不使用have got to,如:
I don't usually have to work on Sundays.通常我在星期天不必工作.
I often have to get up at 5.我常常不得不5点钟起床.
看下面两个句子：
Jim's got to check the temperature every 12 hours.
Jim has to check the temperature every 12 hours.
have got to 一般没有“习惯性”的含义,而且,当它和具有动态意义的动词连用时,常常是指将来…….第1句可能含有指示,命令的意思,规定吉姆将来的职责；而第2句更加可能是表示一种习惯性动作（这就是吉姆现在的职责了）.
have to 与 have got to的另一区别,就是后者不大用于过去时,如：
They didn't have to worry about money.他们那时不必为金钱而操心.
I had to walk very fast to catch up with you.为了赶上你,我不得不走得很快.
最后一个区别,就是have to 前可加助动词或情态动词,或者用在进行时和完成时结构中,而have got to却不能,如：
I shall have to help him as much as I can.我不得不尽我所能去帮助他.
He may have to cancel his plan.他也许不得不取消他的计划.
People are having to boil their drinking water during this emergency.在这个紧急状况下,人们必须煮沸他们的饮用水.
The administration has had to make unpopular decisions.行政部门不得不做出不得人心的决定.
