Expressing necessity : MUST , HAVE TO , HAVE GOT TO

Expressing necessity : MUST , HAVE TO , HAVE GOT TO

MUST and HAVE TO both express necessity

Example :

a. All applicants must take an entrance exam

b. All applicants have to take an entrance exam

Note : it is necessary for every applicant to take an entrance exam. There is no other choice. The exam is required

In everyday statements of necessity, have to is used more commonly than must . must is usually stronger than have toband can indicate urgency or stress importance.

Example :

a. I’m looking for sue. I have to talk to her about our lunch date tomorrow. I can’t meet her for lunch because I have to go to a business meeting at 1:00

b. Where’s sue ? I must talk to her right away. I have to urgent message for her

note :

In (a) : the speaker is simply saying, “ I need to do this, and I need to do that. “

In (b) : the speaker is strongly saying, “ this is very important !“

Have to is usually pronounced “hafta”;

has to is usually pronounced “ hasta”

Example :

a. I have to (“hafta”) be home by eight

b. He has to (“hasta”) go to a meeting tonight

Have got to also expresses the idea of necessity:

Example :

a. I have to go now. I have a class in ten minutes

b. I have to go now. I have a class in ten minutes

Note :

a and b have the same meaning. Have got to is informal and is used primarily in spoken english. Have to is used in both formal and informal english

Usual pronounciation of got to is “gotta”. sometimes have is dropped in speech: “ I gotta do it”

Example :

- I have got to go ( “ I have gotta go / I gotta go”)  now

The idea of past necessity is expressed by had to. There is no other past form for must ( when it means necessity ) or have got to

Exercise : MUST , HAVE TO , HAVE GOT TO.

Directions : Answer the question. Practise pronouncing the usual spoken forms of have to and have got to 

1. what are some of the things you have to do tday or tomorrow ?

2. What does ……. have to do todays ?

3. What have you got to do after class ?

4. What has ………….. got to do after class ?

5. Can you think of something very important that you must do today or tomorrow ?

6. What is something that you had to do yesterday ?

7. Ask a classmate a question using have to and what time/where/how often/why.*

* a form of do is used with have to inquestions : e.g., when does he have to leave ?

Lack of necessity and prohibition : have to and must in the negative

When used in the negative , must and have to have different meanings

Lack of necessity

a. Tomorrow is a holiday. We don’t have to go to class

b. I can hear you. You don’t have to shout

Do not have to = lack of necessity in (a) it is not necessary for us to go to class tomorrow because it is a holiday.

Must not = prohibition ( do not do this )

Prohibition

a. You must not look in the closet. Your birthday present in hidden there.

b. You must not tell anyone my secret. Do you promise ?

Note : negative contraction : mustn’t ( the first “t” is silent:”muss-ent”)

- lack of necessity may also be expressed by need not + the simple form of verb : you needn’t shout .the use of needn’t as an auxiliary is chiefly Britihs Except in certain common expressions such as “ you needn’t worry “

Exercise : HAVE TO and MUST in the negative

Directions : use must not or do not have to in the following

1. I’ve already finished all my work, so I don’t have to study tonight. I think I’ll read for a while

2. I must not forget to take my key with me

3. You ……………… introduce me to Dr.Gray. We’ve already met

4. In order to be a good salesclerk, you ……………….. be rude to a costumer

5. A person …………….. become rich and famous in order to live a successful life

6. Johnny ! you ………. play with sharp knives. Put that knife down immediately!

7. I …………….. go to the doctor. I’m feeling much better

8. We ………..go to the concert if you don’t want to , but it might be good

9. Robin ! what are you doing ? no, no, no. You ……………….put your vitamin pill in your nose!

10. Bats ………….see in order to avoid obstacles. They can navigate in complete darkness

11. If you encounter a growling dog , you ……………… show any signs of fear. If a dog senses far, it is more likely to attack person.

12. A person ……….. get married in order to lead a happy and fulfilling life

Exercise : HAVE TO and MUST in the negative

Directions : complete the sentences with your own words

Possible response : students in elementary school don’t have to pay tuition

Example : students must not ……………

Possible response : students must not cheat during tests

1. children must not ………….

2. Children don’t have to …….

3. Drivers must not …………

4. Drivers don’t have to …….

5. We don’t have to ……..

6. We must not …………..

7. ….… doesn’t have to ……..

8. ….….. must not …..

9. Waiters must not …….

10. Waiters don’t have to …….

11. I don’t have to ……

12. I must not ………