1. OBLIGATION MUST AND TO HAVE TO

2. Must is a modal verb. It is used in the present or future. Must has no final s in the third person singular: You must, he must Must takes the bare infinitive: I must eat it up not I must to eat it up. To Have to is a verb with all tenses.It´s a normal verb like to read, to write, to paint.... She has to brush her teeth after the meals. They will have to wear uniforms next winter.

3. Must and Have to I have to do something: it is necessary to do it, I am obliged to do it, it´s a rule, it´s the law, it´s a general obligation. You have to take this medicine three times a day. I must do something: You think it is necessary to do something, you give your opinion, it´s your personal obligation. I must do the ironing-there´s a pile of clothes which need to be ironed.

4. Fill in the gaps:must or have to? She __________ wear gloves at work. She has to wear gloves at work.(it´s the rule in her job) I _________buy some milk-there isn´t any in the fridge. I must buy some milk-there isn´t any in the fridge.(my personal obligation) You can´t go straight on along Main Street. You _______ turn right. You can´t go straight on along Main Street. You have to turn right.( there´s a traffic sign) You can´t park outside the police station for nothing. You __________pay. You can´t park outside the police station for nothing. You have to pay. ( it´s the law) I eat too much pasta. I really __________stop. I eat too much pasta. I really must stop.( it´s my personal obligation.I think I´m getting fat)

5. STRONG RECOMMENDATION ADVICE MUST- TO HAVE TO- SHOULD/ SHOULDN´T- OUGHT TO /OUGHT NOT TO Strong recommendation: We use must and to have to. Yesterday I went to the cinema to see « Agora ». You have to see this film. It´s great. You must see this film. It´s nice Advice: We use should and ought to (and negative forms) Should is less stronger than must /to have to. You should do something=it´s a good thing to do, it´s the right thing to do. You shouldn´t do something=It´s not a good thing to do. We often use I think, I don´t think, Do you think... with should.Ex.: I think she should go home.It´s getting darker and darker or I think she ought to go home.

6. PROHIBITION MUSTN´T

7. It´s a negative imperative: Don´t… You mustn´t cross this line (Don´t cross this line) You mustn´t have your mobile phones on.(Don´t have your mobile phones on) (Don´t You mustn´t play the music so loud-your dad is sleeping right now. (Don´t play the music so loud) Mustn´t=can´t/ aren´t/isn´t allowed to In Dublin, you can´t smoke in any bars. In Spain, you aren´t allowed to smoke in public places. You mustn´t smoke on a plane. It isn´t permitted.

8. NO OBLIGATION LACK OF NECESSITY DON´T HAVE TO / NEEDN´T / DON´T NEED TO

9. It´s not necessary to do it You don´t have to come to class next Friday because we are taking it off. From 9 to 10 she doesn´t have to pay for the drinks. They are all free. I´m not working tomorrow so I don´t have to get up at 7. They needn´t pay ( They don´t need to pay)for the cinema. It´s free for all teenagers in summer holidays. We needn´t make up our minds now.(We don´t need to make up our minds now). We can decide a little bit later. Mary has got enough sugar for the cake so she doesn´t need to go shopping.

10. It was easy, wasn´t it? The end