A: Why do you have to leave?
B: I don't have to, but I should. It's late.
Form
Need to and have to are not modal verbs, but they are used in a similar way. Study the following form for the past and present:
Positive Sentences
|
I You We They |
need to have to |
go. study. sleep. |
|
needed to had to |
||
|
He She It |
needs to has to |
|
|
needed to had to |
Negative Sentences
|
I You We They |
do not (don't) did not (didn't) |
need to have to |
go. study. sleep. |
|
He She It |
does not (doesn't) did not (didn't) |
Yes / No Questions
|
Do Did |
I you we they |
need to have to |
go? study? sleep? |
|
Does Did |
he she it |
Short Answers
|
Yes, (I / you / we / they) do / did. Yes, (he / she / it) does / did. |
|||
|
No, (I / you / we / they) don't / didn't. No, (he / she / it) doesn't / didn't. |
Wh Questions
|
Where When Why What time ... |
do did |
I you we they |
need to have to |
go? study? sleep? |
|
does did |
he she it |
Use
Have to and need to have a similar meaning to must. They are used to describe obligations or things that are necessary to do:
I have to do my homework.
I need to do my homework.
I must do my homework.
Michelle has to leave soon.
Michelle needs to leave soon.
Michelle must leave soon.
Must does not have a past form. Use had to or needed to instead:
Yesterday, I must had to / needed to wake up early.
When I was a child, I must had to / needed to practice the piano every day.
This morning, I must had to / needed to take the bus because my car didn't start.
Must cannot be used with will or be going to. Use have to or need to instead:
We will have to / need to pay a tip.
I'm going to have to / need to study hard next year when I go to university.
In questions, English speakers usually use have to or need to instead of must:
Why do I have to / need to eat these vegetables? I don't like them!
Does Leanne have to / need to work tomorrow?
Negative
As we have studied, must has a very similar meaning to have to and need to. This is only true in positive sentences. In negative sentences, their meanings are very different:
Mustn't
"You mustn't do that!" = "It is not okay to do that."
As we studied in Grammar 8-2, mustn't is used for negative obligations. It is used to mean, "Don't do it!"
You mustn't smoke here.
You mustn't touch this!
(Not) Have to / Need to
You don't have to / need to do that = It is not necessary to do that.
When we use have to or need to in negative sentences, it means something is not necessary or important to do. You can do it if you want, but it is not necessary.
I don't have to / need to study tonight because I don't have a test tomorrow.
Bill doesn't have to / need to work tomorrow.
Notice the differences:
You mustn't drive. You are too sleepy.
You don't have to drive. I can do it.
Exercise
Open the exercise to begin the activity. Follow the instructions in the document.