Can/Could/May/Will/Would. Can/Could/Be Able To

Module 5
Can/could/may/will/would
* We use Can I…?, Could I…?, May I..? to ask for, give and refuse permission.
Can/Could/May I go to the party?
Yes, you can/may
No, you can’t/may not
* We use Can I…?, Could I…?, May I..? to offer help and make request.
Can/Could/May I help you?
Can/Could/May I have some more cake?
* We use Can/Could/Will/Would you…? to make polite request andask for a favour. Could and Would are more polite.
Can/Could/Will/Would you help me with my homework?
Must/have to/need (to)/can’t
* We use must and have to to express obligation.
I must buy Sam a present for his birthday
You have to be at work by 8:30
* We use need to to express necessity
I need to talk to you
* We use don’t have to, don’t need to and needn’t to expresslack ofnecessity/obligation
You don’t have to go out with her if you don’t like her
You don’t need to give me back the money
She needn’t buy me a present
* We use mustn’t and can’t to express prohibition
You mustn’t/can’t speak during the lesson

Note: To express obligation in the past, we use had to
To express obligation in the future, we use will have to

Note: Need means thatsomething is necessary. It is used:
* As a main verb in all tenses, in the affirmative, negative and question form. It is followed by a full infinitive and forms the negative and question form with auxiliary verbs.
* As a modal verb only in the negative and question form of the present simple. It is followed bya bare infinitive and forms the negative and question form without auxiliary verbsAFFIRMATIVE |
IHe/She/ItWe/You/They | need to goneeds to goneed to go |
NEGATIVE |
I don’t need to go He/She/It doesn’t need to goWe/You/They don’t needto go | I He/She/It needn’t go We/You/They |
QUESTIONS |
Do I Does he/she/it need to go?Do we/you/they | INeedhe/she/it go?we/you/they |

Can/could/be able to
* We use can to express ability in the present.
The baby can speak
* We use could to express ability in the past.
I could climb trees when I was young
* Be able to expresses ability and forms all tense. It is mainly used in tenses where we cannot use can.
He’ll be able to play football on Saturday
May/might/could
* Weuse may, might and could to express possibility in the present or future. Might expresses slight possibility
We may/might/could go to the Summer Festival next weekend
Note: We use may not/ might not to express lack of possibility in the present or future.
Henry may not/might not be able to join us
Must/can’t
Must and can’t express a logical deduction and refer to present.
* We use mustto express a positive deduction.
John has been working all day. He must be tired.
* We use can’t to express a negative deduction
Sue can’t be at home. I saw her at the bus stop five minutes ago.

Modulo 5
Nota: Los verbos están conjugados con el pronombre “yo”, pero se pueden conjugar con otros pronombres
Puedo/ podría/may /will/would
* Usamos el ¿puedo..?, ¿podría..?, ¿may…? parapreguntar, dar y pedir permiso.
¿Puedo/Podría/may ir a la fiesta?
Si puedes/may
No puedes/may
* Usamos el ¿puedo..?, ¿podría..?, ¿may…? para ofrecer ayuda o pedir algún requisito
¿Puedo/podría/may ayudarte?
¿puedo/podría/may tener un poco más de pastel?
* Usamos el ¿puedes/podrías/will/would..? para hacer formales requisitos y para pedir un favor. Podría y would son más formales¿puedes/podrías/will/would ayudarme con mi tarea?
Deber/tener que/ necesitar (que)/no puedo
* Usamos el verbo deber y tener que para expresar obligación.
Debo comprarle a Sam un regalo para su cumpleaños
Tienes que estar en el trabajo por las 8:30
* Usamos el verbo necesitar que para expresar necesidad
Necesito hablar contigo
* Usamos el no tengo que, no necesito que y needn’t , con...