HAVE TO (Tener que)

-Use HAVE TO express a strong obligation.

“The doctor said to me that I have to stop smoking”

”I have to arrive at work at 9 o'clock”My boss is very strict.

”My husband's an interpreter; he often has to go to New York”

HAVE TO (tener que)

1) There is 3rd person singular.

He has to study for the exams.

2)Questions and negatives are made with “do”.

Do I have to go?”NOT have I to go?

What time does she have to get up in the morning?

Do I have to buy a grammar book?

3)We use the infinitive with “to”

Eg.I have to get up at 7.

NOT I have get up at 7.

4) Past tense is had to.

She had to work very hard.

He had to study very hard last year.

5)Don't contract have or has. I have to go. NOT I've to go.

6) “have to” isn't the same as “have got”.

“ I have got a car”(possession)

I have to get up early to catch a plane” (obligation)

Don't have to (No es necesario)

DON'T HAVE TO= Use it to say that something isn't necessary or obligatory.

“You don't have to get a visa(=visado) to go to Scotland).

“Children don't have to go to school on Saturday”

“He doesn't have to work at Easter. He has holidays.”

MUST

We use MUST to express a strong obligation.

“I must do some more work;I want to pass my exam”

“I must stop smoking.

“We must go to New York soon and see your mother.

MUST

1)Must and mustn’t is the same for all persons. There is no-s in the 3rd person singular.

Eg. She/He/ must study for the exams.

NOT She/He musts study for...

2)Questions and negatives are made without “do”.

Eg. Must you go?He mustn't worry.

NOT Do you must go?You don't must worry.

3)We use the infinitive without “to”of other verbs.

Eg.I must write to my mother

NOT I must to write to my m.

4)Must has no infinitive or participle and it has no past tense.(=had to)

NOT (to must, musting, musted do not exist).

She had to work very hard.

MUSTN’T

-Usemustn't+infinitive without “to” to say that it is wrong to do things, it is prohibited. Can't is also possible.

“You musn't open this parcel until Christmas Day”

“you mustn't drive on the left”

DON'T HAVE TO/MUSTN'T

They have completely different meanings:

“you mustn't leave the door open= it is important that you don't leave it open. Don't leave the door open.

“you don't have to leave the door open”=you can leave it open if you want, but it isn't obligatory/necessary.

You mustn't park here = it is important not to park here = don't park here.

“You don't have to park here = it isn't obligatory or necessary. It's your decision.

DON'T HAVE TO/MUSTN'T/MUST

1. Larry_______go to the bank, he hasn't got any money.

2. You ________ smoke in the baby's room.

3. You _________ pay. The entrance is free.

4.In the company everybody ______ start work at 8.30.

5. She _________ work. Her husband earns enough money.

6. I________ pick up my sister from the airport tomorrow.

7. You _________ smoke at the petrol station.

Signs

3. You ____ stop to let other cars pass.2. You _______ pay

to visit the museum

1. You __________ walk to the beach. You can cycle.

Signs

6. You ______ drive faster than 90km/h

5. You ________ give way at the roundabout.

4. You ________wear a suit and tie on Fridays