Mini Lesson: using have to, supposed to, and ought to

Have to is the same as must. It implies that you don't have a choice.

John has to go to work everyday.
The students have to study tonight.

To be supposed to means an obligation. It is something that you should do, or something that another person expects you to do. Don't forget to use the verb be in front of supposed to.

Sally is supposed to meet her friend tonight.
All of the employees are supposed to attend today's meeting.

Ought to means a suggestion. You should do something but you don't have to do it.

We ought to clean the house tonight.
Phillip ought to help you with your homework.

(Notice that all of these words are modals. They are followed by a verb.) 

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You may feel confused about the slight differences between these words. Just think about what the speaker is implying.

I have to do my homework.  (If I don't, will be in trouble.)
I am supposed to do my homework. (If I don't, my teacher will notice that I didn't do it.)
I ought to do my homework. (I don't have to if I don't want to, but I feel I should do it because I want to do well in the class.)

Check Your UnderstandingChoose the best answer.1. Willy needs money to pay for his food and house. If he doesn't go to work, he won't have money. He must work.

Willy ___ go to work.

a. ought to
b. has to
c. is supposed to
2. Johnny should help his mother with the housework. His mother would be happy if he did. But if he didn't help her, his mother wouldn't feel bad.

Johnny ___ help his mother.

a. ought to
b. has to
c. is supposed to
3. Joan want to be a nurse. To become a nurse it is necessary to go to nursing school.

Joan ___ go to nursing school if she wants to be a nurse.

a. has to
b. is supposed to
c. ought to
4. Tom's friend is waiting for him at the gym. They made plans to meet at 6:00. His friend will be upset if Tom doesn't go.

Tom ___ meet his friend.

a. ought to
b. has to
c. is supposed to
5. Lisa tells Nathan that he would be a good manager. She suggests that he apply for a job as a manager. Nathan is going to think about that.

Lisa thinks Nathan ___ be a manager

a. ought to
b. is supposed to
c. has to


Answers
1.b
2.a
3.a
4.c
5.a