首先一点，在表示一次性动作的“必须”找个意义时是可以互换的：

I have (got) to be back by ten.

我必须十点前返回。

I haven’t got to work tomorrow.= I don’t have to work tomorrow.

我明天不必上班。

区别是：

1.当表示经常性动作时，尤其是当句中含有表示经常性的副词，如always, often, ususally，sometimes等时，用have to，而不用have got to。

She doesn’t usually have to work at weekends.

通常她周末不用上班。

Women very often have to juggle work with their family commitments.

妇女经常得两头兼顾，既要工作又要照管家庭。

Nurses often have to contend with violent or drunken patients.

护士经常不得不对付粗暴的或喝醉酒的病人。

Women who carry cash about in the streets, as they very often have to, are a very soft target.

必须经常携带现金上街的女性特别容易受到攻击。

To achieve one's goal, people often have to learn new skills.

为了达到目标，人们常常需要学习新技能。

Why do they always have to resort to violence?

为什么他们总是非要诉诸暴力不可呢？

Why do you always have to echo back my opinions like this?

你为什么总是这样非附和我的意见不可呢？

You always have to pay it back.

你总是要付出代价的。

2、have got to不大用于过去式；have to构成否定句和疑问句时要加do，而have got to只需用have或has构成。

You did not have to be a clairvoyant to see that the war would go on.

就算没有未卜先知的能力也能料到战争会持续下去。

《柯林斯高阶英汉双解学习词典》

She faked illness so that she did not have to go to school.

她装病，这样就可以不去上学了。

They didn't have to pay tax.

他们不必交税。

They didn't have to do anything except sit back and enjoy life.

他们只需置身事外，享受生活。

They wrote back to me and they told me that I didn't have to do it.

他们回信告诉我说不必那么做。

It didn't have to be the Ivy League, but it needed to be "top school."

它不必是常春藤盟校，但它必须是“顶尖学校”。

Traditionally, farmers sold their food in the local market, so the food didn't have to travel very far.

一般传统是农民在当地市场出售食品，这样免去了长途运送的麻烦。中考真题 2015 南京

They didn’t have to worry about money.

那个时候他们不必为金钱操心。

I had to walk very fast to overtake you.

为了赶上你，我不得不走得很快。

He had to go to （the） hospital for treatment.

他不得不去医院接受治疗。

I had to wait half an hour for a bus.

我得等半小时的公共汽车。

My car had to have a new engine.

我的汽车得换一个新发动机。

They had to take a 20% cut in pay.

他们不得不接受减薪20%。

We had to take out a second bond on the property.

我们得申请第二按揭以购买这个房产。

She had to push herself forward to get a promotion.

她必须努力表现自己以求得升迁机会。

She had to write a report on the project.

她必须就这个项目写一份报告。

The general had to get his troops across the river.

将军必须让部队过河。

They had to draw lots to decide who would go.

他们只得抽签决定谁去。

He wasn't well, so we had to leave him behind.

他身体不适，因此我们只好把他留下。

The weather got so bad that we had to turn back.

天气变得非常恶劣，我们不得不循原路折回。

I'm truly sorry that things had to end like this.

事情落到这样的结局，我从内心里感到歉疚。

The doctor said I had to stay in bed.

医生说我必须卧床休息。

He had to mortgage his house to pay his legal costs.

他不得不把房子抵押出去来付诉讼费。

We had to put new locks on all the doors.

我们只好把所有的门都安上新锁。

have to的特殊疑问句形式

What do you have to do on Sundays？在星期天你得干什么？

Why does she have to move to Paris？她为什么得迁往巴黎？

Where do they have to work？他们必须在哪里工作？

Have you got to go?

你非得走吗？

《牛津高阶英汉双解词典》

The state has got to find some way to balance these two needs.

国家必须找出平衡这两种需求的办法。

This war has got to end soon.

这场战争必将很快结束。

Someone has got to get things moving.

应该有人牵头把事情做起来。

There has got to be a degree of flexibility.

得有一点灵活性才行。

Learning has got to be active and experiential.

学习必须积极，而且要汲取经验。

3、have to前面可加助情态动词或动词，或用进行体、完成体结构中，而have got to不能。

You shouldn't always have to kill yourself to do well.

你不该总是为了做到尽善尽美而累坏自己。

The point is you shouldn't have to wait so long to see a doctor.

关键是不该等那么长时间才看病。

The only dark cloud on the horizon was that they might have to move house.

唯一的忧虑是他们可能要搬家。

On Monday he would have to return to his regular duties.

星期一，他就得回去正常上班了。

If he agreed to their demands, he would have to be untrue to his own principles.

假使答应他们的要求，他就得背叛自己的原则。

He would have to accept it; there was no other way.

对此他将别无选择，只有接受。

Everyone would have to work hard together to rebuild the economy.

所有人都应该一起努力以重建经济。

I would have to learn, little by little, to exist alone.

我得慢慢学会独自生活。

You would have to dig up the plant yourself.

你得自己把那株植物挖出来。

If they wanted a deal at any price, they would have to face the consequences.

如果他们无论如何都想达成交易，他们就得承担其后果。

Any such action would have to be approved by both American and Saudi leaders.

任何这样的行动都必须获得美国和沙特领导人双方的批准。

You would have to be pretty hard-hearted not to feel something for him.

只有铁石心肠的人才会对他无动于衷。

If someone tried to bash my best mate they would have to bash me as well

如果谁想揍我最好的朋友，那我就跟他拼了。

He opined that the navy would have to start again from the beginning.

他认为海军将不得不再度从零开始。

He told her their affair would have to stop, because Jack Smith was blackmailing him.

他告诉她说他们的婚外情必须结束了，因为杰克·史密斯正在敲诈他。

I shall have to miss the party, worse luck!

我参加不了这次聚会了，真倒霉！

We shall have to explicate its basic assumptions before we can assess its implications.

在评估它的影响之前，我们应该解释清楚它的基本假设

We shall have to mow down the tall grass in the big field.

我们得把大田里的高草割掉。

If we don't receive a reply by tomorrow morning, I shall have to get on to him.

如果明天早上我们得不到答复，我们还得和他联系。

We have had to adapt quickly to the new system.

我们不得不迅速适应新制度。

No American should have to drive out of town to breathe clean air.

所有美国人都不必开车到城外去呼吸洁净的空气。

We may have to take military action.

我们可能不得不采取军事行动。

Government sources indicated yesterday that cuts may have to be made.

政府方面昨天透露，削减可能势在必行。

They may have to widen the road to cope with the increase in traffic.

他们可能得拓宽这条道路以适应车辆的增多。

We may have to intervene militarily in the area.

我们可能只好对这一地区进行军事干涉。

There are rumblings that the election may have to be postponed.

有传言说选举也许不得不延期。

We’ll have to borrow the money we need.

我们需要的这笔钱只好去借了。

We may have to take military action.

我们可能不得不采取军事行动。

You'll have to move ─ you're in my way.

你得挪一挪，你挡了我的路。

Sooner or later you will have to make a decision.

你早晚得拿个主意。

I'm going to have to find a new apartment pretty soon.

我很快就得找个新住处了。

Don't give me that line about having to work late again.

别再跟我说不得不工作到很晚这样的话。

I'm always having to clean up after the children.

孩子们离开以后，我总得打扫一番。

What gets me is having to do the same thing all day long.

使我感到烦恼的是整天都得干同样的事。

The worst part was having to wait three hours in the rain.

最糟糕的是必须在雨中等待三个小时。

She shouldn't be having to deal with problems like this at such a tender age.

她小小年纪涉世未深，实在还不该处理这样的问题。

Just as large companies are having to cut back, so small businesses are being forced to close.

大公司不得不紧缩，小企业则被迫关闭。

With the price increases, we are all having to tighten our belts.

由于物价上涨，我们都只好勒紧裤腰带了。

People are having to think hard about their holiday plans.

人们现在得仔细地琢磨自己的度假计划。

They are still having to live on very low incomes.

他们现在还得靠微薄的收入过日子。

People are having to boil their drinking water during this emergency.

在这个紧急状况下，老百姓必须煮沸腾他们的饮用水。

The administration has had to make unpopular decision.

行政部门不得不做出不得人心的决定。

He has had to be in every day.

他每天都得坐班。

He has had to travel the country in search of work.

他不得不走遍全国寻找工作。

Her company has had to split up and work from two locations.

她的公司不得不被拆开，分在两处办公。

The company has had to make redundancy payments of £ 472 million.

该公司不得不为裁员支付4.72亿英镑的补偿款。

He has had to eat his words about the company being recession-proof.

他不得不收回他说过的公司能免受经济衰退影响的话。

He has had to give up luxuries as he scrimps and saves while looking for a job.

找工作期间，他只好放弃奢侈的生活，精打细算、省吃俭用。

My personal life has had to take second place to my career.

我的私人生活不得不为事业让路。

He has had to shoulder the responsibility of his father's mistakes.

他得为他父亲的过错承担责任。

She has had to cope with losing all her previous status and money.

她不得不忍受彻底失去以前所拥有的地位和金钱的痛苦。

We have had to adapt quickly to the new system.

我们不得不迅速适应新制度。

We have had to raise our prices because of rising costs.

因为成本日益上涨，我们不得不提高价格。

In some cases people have had to wait several weeks for an appointment.

在某些情况下，人们必须等上好几周才能得到约见。

They have had to adapt themselves to a war economy.

他们不得不适应战时经济。

Other industries have had to sack managers to reduce administrative costs.

其他行业只得精简管理人员以减少行政开支。

I have had to pay for repairs to the house.

我不得不支付房屋维修费用。

They have had to seek work as labourers

他们只好找体力活儿干。

The landowners have had to sell their private aircraft.

这些土地所有者不得不卖掉自己的私人飞机。

We have had to ask the agency and their client to tone their ads down.

我们不得不要求广告公司及其客户将他们的广告处理得低调些。

We have had to contend with the disinterest of much of the medical profession about this topic.

我们必须全力对付很多医疗界人士对这一话题的冷漠。

I have had to spend a lot of money having my house replumbed and rewired.

我只好花了一大笔钱给房子重新布线铺管。

The hotels are full up, and the guests have had to go to this dinky little motel way out on Stewart Avenue.

宾馆已经客满了，客人们不得不到斯图尔特街上这家偏远的小汽车旅馆里来。

Most manufacturers have had to introduce short-time working.

大多数制造商不得不推行短工时工作制。

His council had had to perform miracles on a tiny budget.

他的委员会不得不以极少的预算去创造奇迹。

If she had had to give up riding she might have taken up sailing competitively

如果她当时不得不放弃骑自行车的话，她或许就从事她很有优势的帆船运动了。

The police had had to deal with some of the most ferocious violence ever seen on the streets of London.

警方不得不去处理伦敦街头发生的一些极其严重的暴力事件。