Modal verb “Can and Could”

EXAMPLES:
*You could be wrong.
*This new plan could be very risky.
*I couldn’t watch the T.V. If I don’t do my homework.
*We couldn’t leave you alone.
*Could you open the window?
*Could we go to the stadium on Saturday?

(to ask something)

Can + infinitive (can do / can play / can come etc.):

? Could +     :)        + Verb + comp.?

S. A. Yes,               could    No,         couldn’t

Modal verb “Must, mustn´t and don´t need to”

EXAMPLES:

*He must have a lot of money.
*You mustn’t move to London.
*We mustn’t spend the money.
*Must you go to school?
*Must we visit your parents?

(Obligation: rules, prohibitions)

Must + infinitive (must do/ must work etc.):

+ J + must + verb to + comp.

- J + mustn´t + verb + comp.

? must  + J + verb + comp.

S.A Yes, J must            No, J mustn´t

Modal verb “ I have to”

EXAMPLES:
*They have to leave early.
*John has to wear a tie at work.
*You don’t have to eat that.
*Did you have to go to school?
*Do you have to work on Saturday? Yes, I do

(Obligations “persona”)

Present

Past

+J + have/has to + verb to + comp.

- J + don´t/doesn´t + have to + verb + comp.

? Do/does + J have to + verb + comp.

S.A Yes, J have/has to            No, J don´t/doesn´t have to

Modal verb “Should”

EXAMPLES:

*You should buy some new shoes.

*We should stop car
*what time do you think you should go home?I should 1:00 am

(Recomendation)

Sholud + infinitive

(should do/ should watch etc.):

+ J + should + verb to + comp.

- J + shouldn´t + verb + comp.

? Should  + J + verb + comp.

S.A Yes, J should           No, J Shouldn´t