Use of Must vs Have to, Has to, Had to

We use MUST vs HAVE to, HAS to, and HAD to when we do something under Compulsion, Obligation, and Necessity (things that are essenvertial to do).

Differences between Must vs Have to / Has to

1. The model verb must = is even stronger than have/has to.
2. Must is more formal and is stronger than have to.
3. Must is used for a forceful obligation on compulsory demand.
4. Has/have/had to are used for a general kind of obligation, necessity, and compulsion.

Use of MUST

In the affirmative form, have to or has to is very similar to the modal verb must, except must is even stronger than have to.

Examples of Must:

• The government must maintain the law and order.
• You must renew your driving 🚘 license.
• They must give up smoking 🚬 now.
• I must go to a meeting in an hour.
• You must take your pills every night before bed.

Use of Has to / Have to

In all of these examples, we are talking about obligations or things that are necessary to do. So, have/has to in the present tense is talking about something necessary or an obligation. I have to do now in the present tense. And had to refer to the past: yesterday, last week, etc.

Conjugating the verb have to / has to

• I = have to + V1^st + Complement.
• You = have to + V1^st + Complement.
• We = have to + V1^st + Complement.
• They = have to + V1^st + Complement.
• He = has to + V1^st + Complement.
• She = has to + V1^st + Complement.
• It = has to + V1^st + Complement.

Examples of Must vs Have to / Has to

• I have to go to a meeting in an hour.  
• You have to take your pills every night before bed.
• My dad has to wake up at 5 am to go to work.  
• She has to move out of her apartment by July.
• I have to clean the bedroom.
• He has to buy a new toolbox.
• We have to attend the session on Monday.

Use of Had to

So, what is the difference between have to, has to, and had to? Well, had to be in the past tense.

For example:

• She had to bring up her children after the divorce.
• I had to book a hotel before the summer vacation.
• They had to combine their efforts to win the game.
• You had to work day and night to succeed in life.
• I had to leave my car overnight with the mechanic to get repaired.

So, imagine yesterday, it was necessary, I had to get my car fixed and leave the car overnight at the mechanics.

And now today, in the present tense, I could say I have to pick up my car this afternoon from the mechanic.  

Negative Forms of Must not vs Have not to / Has not to

Now let’s talk about have to or has to in the negative form. We use don’t have to or doesn’t have to = to say that something is not necessary or is not an obligation. So, it is essentially optional.  

Examples of Must not

• You must not violate the traffic 🚥 rules.
• I must not tolerate the harsh attitude of my servant.
• They must not arrive here in my presence.
• We must not stand in between the road.
• The students must not cheat in the papers.

Examples of Have not / Has not

• I don’t have to quarrel with you.
• You don’t have to quarrel with me.
• He doesn’t have to quarrel with us.
• She doesn’t have to quarrel with her friends.
• It doesn’t have to quarrel at all.
• We don’t have to quarrel with anyone.
• They don’t have to quarrel with others.

More examples:  

You don’t have to come to my party if you don’t want to. This means it’s not an obligation. If you don’t want to come to my party, you don’t need to come. You don’t have to come.  

• James doesn’t have to do any homework tonight.
• You don’t have to pay for my services.
• He/ She doesn’t have to stay here tonight.
• Mom doesn’t have to drive me there tomorrow.
• You don’t have to come tomorrow if you don’t feel like it.  
• The children don’t have to wear school uniforms on Friday.
• We don’t have to pay for the hotel room until we check out.

Interrogative Forms of Have to, Has to

Now let’s talk about have to and has to in the interrogative form and how we make questions. We use do I have to ask if something is necessary or an obligation. You often hear children ask this question:  

Do I have to? Is it necessary? So, we say:

• Do you have to?  
• Do they have to?
• Does she have to?
• Does it have to?
• Do we have to?
• Do they have to?

Examples

• Does he have to go to school tomorrow?
• Does she have to arrive early?   
• Do I have to eat all my vegetables?
• Do you have to work late tonight?
• Does he/ she have to book this room?
• Does Brandon have to come to church on Sunday?  
• Do you have to tolerate the harsh attitude of your boss?

Practice quiz with have to or has to

So, complete these sentences in the correct form of = have to, has to in the present tense.

• I _____ study for my exam tomorrow.  
• Brittany _____ take antibiotics for five days.
• You _____ come tomorrow if you don’t feel like it.
• We _____ arrive early?
• Mom _____ drive me there tomorrow.

Note a Correction 

You have to study for your final exams. Now, you cannot say you’ve to study. With have to, we do not use the contraction.