1. Modal verbs

2. Ability: can/can’t, could/couldn’t CAN/CAN’T for things we are able to do generally or at the moment She can speak Japanese (she is able to speak Japanese) I can see the moon I am able to see the moon now) COULD/COULDN’T for past abilities WILL BE ABLE TO for future abilities

3. Can/Could I? May I? Could you? Can/Could I? May I? to ask permission. Could/May I? more formal Could I have two tickets please? Can/Could to give permission You can go out tonight For something allowed in general rather than for a particular person, we use CAN People can drive on the roads when they are eighteen BUT in official notices MAY Bags may be left here Can/Could/Would you? (not MAY YOU) to aske someone to do something Could you close the window?

4. Must/Have to MUST When the speaker thinks it is necessary/important to do an action You must clean your room HAVE TO When something is compulsory In England you have to wear a uniform to go to school

5. Mustn't/Don't have to MUSTN'T To say that smth is against the rules/laws You mustn't smoke on buses (it's against the rules) DON'T HAVE TO To say that smth is unnecessary You don't have to learn Latin at school (you're not obliged to do that)

6. Must/can't/may/might/could CERTAINTY → MUST The Greens have two houses and two cars. They must earn a lot of money IMPOSSIBILITY → CAN'T Mark studied a lot for his exams, but he got poor marks; he can't be very clever POSSIBILITY → MAY MIGHT COULD 1) She may be in the garden (= perhaps she is in the garden 2)

7. Should/Shouldn't SHOULD To say that smth is a good thing for us to do You should do your homework To give positive advice You should eat more fruit (= It's a good idea) You must eat more fruit – said the doctor (= it's very important) SHOULDN'T To say that smth is a bad thing for us to do You shouldn't stay in the sun all day To give negative advice You shouldn't drive so fast (= it's dangerous)

8. Should/ought to Ought to is different from should. Ought to is generally used to talk about duties of law A: I saw a robbery. What should I do? B: You ought to report to the police (= it is a person 's duty to report it)

9. http://isabelcambridgesiurot.blogspot.it/p/modal-verbs.html