Modal verbs are used to express ideas like ability, permission, obligation, probability and more. They are different from normal verbs in that they don't take an 's' in the third person singular, they form questions through inversion, and they are followed directly by an infinitive without 'to'. Common modal verbs include can, could, may, might, will, would, must, shall, should and ought to. Each modal verb has specific meanings and uses when expressing abilities, obligations, probabilities, habits and more.

1. MODAL VERBS

2. Modal Verbs
can could may might
will would must shall
should ought to

3. Modals are different from normal verbs:
● 1: They don't use an 's' for the third person
singular.
● 2: They make questions by inversion ('she can
go' becomes 'can she go?').
● 3: They are followed directly by the infinitive of
another verb (without 'to').

4. Probability
● Pueden ser usado cuando queremos decir que
tan seguros estamos de que algo suceda, esté
por suceder o sucederá.
● Con frecuencia los llamamos 'modals of
deduction' o 'speculation' o 'certainty' o
'probability'.

5. Ejemplos
● It's snowing, so it must be very cold outside.
● I don't know where John is. He could have
missed the train.
● This bill can't be right. £200 for two cups of
coffee!

6. ESTRUCTURA

7. ● I am waiting for Julie with another friend, David. I
ask: 'Where is Julie?
● David guesses:
1) She must be on the bus. (I'm fairly sure this is
a good guess)
2) She might come soon. (maybe)
3) She could be lost. (maybe)
4) She may be in the wrong room. (maybe)
5) She can't be at home. (I'm fairly sure this isn't
true)

8. Might
● El verbo 'might' expresa débil probabilidad o
posibilidad. Se utiliza cuando queremos decir:
podría, quizás, puede que (They might come
tomorrow).
● I might - podría / quizás / puede que

9. ● They might be waiting for us at the station.
● This might be our only chance
● I might lose my job.
● Harry might write soon.
● You might find a solution.
● Sylvia might not live there anymore.
● We might not know everything.
● It might not rain tonight.

10. Ability
Usamos 'can' y 'could' para hablar acerca de
una habilidad o una capacidad.
● She can speak six languages.
● My grandfather could play golf very well.
● I can't drive.

11. Can
Can es usado para hablar de algo que es generalmente
posible, algo que sabemos que sucederá:
● Prices can be high in London.
Can no es usado para hablar acerca de posibilidades
específicas:
● He could be on the bus (not: 'can be').

12. Could
Podemos usar could + infinitive para hablar
acerca de una posibilidad en general en el
pasado.
● Prices could be high in the sixteenth century.

13. Obligation & Advice
Podemos usar las palabras 'must' or 'should'
para hablar de algo que es necesario o
innecesario o dar un consejo.
● Children must do their homework.
● We have to wear a uniform at work.
● You should stop smoking.

14. Have to
Don't have means you don't need to do something,
but it's fine if you want to do it

15. Must
Mustn't means it's not allowed, or
it's a bad idea

16. Should

17. SHOULD
Should & shouldn't son usados para hacer una
suposición acerca de lo que probablemente
sea verdad, si todo va como se espera.
● They should be there by now.
● It shouldn't take long to drive here.

18. Ought to
● El verbo 'ought to' es igual al 'should' y expresa
una obligación débil. Significa debería, tendría
que.
● I ought to - debería / tendría que
● Helen ought to be more careful.
● I ought to stay in bed.

19. ● We ought to go together.
● They ought to be here already.
● You ought to eat more vegetables.
● Tom ought to take her home.
● It ought to work properly.
● You ought not to drink so much.
● They ought not to go camping without a torch.
● George ought not to wear someone else's
glasses.

20. Permission
Podemos usar verbos auxiliares como: 'can',
'could' y 'may' para pedir y conceder permiso.
También usamos verbos modales para decir
algo que no está permitido.
● Could I leave early today, please?
● You may not use the car tonight.
● Can we swim in the lake?

21. May
Se utiliza para expresar cierto grado de
probabilidad de una acción o grado de certeza:
● It may rain today.
Significa: podría, quizás, puede que.
● We may stay here for the night.

22. Ejemplos
● You may ask three questions.
● I may visit Susan on Monday.
● The road may be blocked.
● Jack may be telling the truth.
● I may not 1come next week.
● That may be a good idea.

23. Shall
●
Se puede utilizar el verbo shall con la primera persona del singular y la
primera persona del plural. Se utiliza para hacer sugerencias, ofrecimientos
así como para recalcar la voluntad de hacer algo.
●
Shall we go to the theatre? (sugerencia)
●
Shall I help you? (ofrecimiento)
●
I shall be going by bus (voluntad firme)
La forma negativa es shall not (shan´t).
●
I shan´t stay here
●
No me quedaré aquí

24. Habits
Podemos usar 'will' y 'would' para hablar acerca
de hábitos o cosas que usualmente hicimos o
no hicimos en el pasado.
● When I lived in Italy, we would often eat in the
restaurant next to my flat.
● John will always be late!

25. Would
● En este sentido, se utiliza para hablar de las
situaciones teóricas:
● I would love to go to Menorca.* It sounds like a
beautiful place.
● I'm sure he would play his guitar for you.** He
never says no.