1. NECESSITY
HAVE (GOT) TO, MUST, CANT

2. HAVE TO, HAVE GOT TO, MUST SHOW THAT
SOMETHING IS NECESSARY.
• Have to is the most common expression in everyday speaking and writing.
Example: You have to carry your bag to school everyday.
• Have got to is used in conversation and informal writing.
Example: I’ve got to do my homework.
• Must is more formal and is much stronger than have to. Only people with power
use it (parents, police, teachers, leaders)
Example: Sophia, you must make your bed before you live.

3. HAVE TO FOR PAST, PRESENT, FUTURE, PRESENT
PERFECT
• Past
Example: She had to work a lot las year.
• Present
Example: He has to work today.
• Future
Example: They will have to work hard next year.
• Present Perfect: are actions that have happened recently and/or actions that still hold true in
the present.
Example: I haven’t had to work this week. Or I have never had to work in my life.

4. NECESSITY
Affirmative Negative Interrogative
Have to Have to/has
to
Don’t have to/Doesn’t have
to
Do … have to/ Does ... Have to
Have got to Have got to/
Has got to
Must Must Must not
Can’t Can’t

5. QUESTIONS
• Use have to for most questions
Example: Do you have to stay in class?
Answer. Yes, I do or No, I don’t
Does he have to stay in class?
Answer: Yes, he does, or No, he doesn’t

6. DON’T HAVE TO AND MUST NOT OR CAN’T
• Don’t have to and must not have very different meaning.
• Use don’t have to, to show that something is not necessary. There is a choice.
Example: I don’t have to be sit all day.
• Use must no to show that something is against the rules. There is no choice.
• We often use can’t instead of must not to express prohibition.
Example: You must not drive without a license. Or You can’t drive without a license.