Past perfect (+) s + had + V3 / V ed + c + M s + had + not + V3 / V ed + c + m (?) Had + s + V3 / V ed + c + M?

HAVE TO
(+) S + have / has + to + bare inf. + C + M
(-) S + do / does + not + have + to + bare inf. + C + M
(?) Do / does + S + have + to + bare inf. + C + M?
(?-) Do / does + S + not + have + to + bare inf. + C + M?
(?-) Don’t / doesn’t + S + have to + bare inf. + C + M?

Have to is used to epress obligation. Have to is used when the situation, law, rule says that it is important to do something.

e.g. You have to go to your school on time.
Today, I have to cook by myself, because my mother is not at home.
Employee have to wear a uniform in our company.
Children under 12 have to wear special seat-belt.

The past form of ,,have to’’ is ,,had to’’.

e.g. We had to wait the next flight.
They did not have to wait the teacher because he was not late.
Did he have to come to to the course at 5 p.m?

Must in the negative form is used in order to prohibit something or give strong advice not to do something. But have to in the negative form is used to say that it is not necessary to do something.

e.g. You must not smoke.
You don’t have to smoke here.
You don’t have to bring your book.
You must not talk in the lesson.
You don’t have to cry if you can’t pass.


NEED
Need is used in order to show that there is necessity or a need to do something.
e.g. I need exchange the tyre.
We need clean our room.
They need buy some coffee and sugar.
I need fix my phone.

Need can be used as an ordinary and auxiliary(modal) verb as well.

Modal version:
(+) S + need + bare inf. + C + M
(+) S + need + not + bare inf. + C + M
(+) Need + S + bare inf. + C + M?
(?-) Need + S + not + bare inf. + C + M?
(?-) Needn’t + S + bare inf. + C + M?
e.g. She need clean the house.
She need not clean the house.
Need she clean the house?
Need she not clean the house?
Needn’t she clean the house?
Ordinary version: