Modals verbs

Powerpoint

Be Able to

Must & Have to

Should & Ought to

Be Allowed to

Mustn't & Don't have to

Will, Would & Shall

Can & Can't

May & Might

Need to | Needn't

Can & Could

Modal Perfects

¿Qué son?

Los modales son verbos que actuan como auxiliares y tienen unas características diferentes a los demás verbos. En este grupo incluimos can, could, may, might, must, mustn't, needn't, should, ought to, will, would y shall.

1. Sólo poseen una forma única para todas las personas, por tanto, no añaden "-s" en la tercera persona singular del presente simple.

I can | He can | He can drive a bus | She must be ill.

2. Carecen de algunos tiempos verbales. Para expresar la idea en los tiempos que les faltan tenemos que emplear otros verbos como be able to, have to, know how to, etc.

I can't swim now, but next year I will be able to swim. (will be able to es el futuro de can)
I must study today because yesterday I had to help my mother (had to es el pasado de must)
We can't do this grammar exercise today, but we will know how to do it next week.

3. No necesitan ningún auxiliar para formar la interrogativa ni la negativa.

He cannot speak English | May I come in?

4. Siempre van seguidos de otro verbo en la forma base.

I must go now | He should listen

5. No tienen infinitivo, es decir, nunca se nombran poniendo "to" delante de ellos.

We are going to study the verbs can and may. Then we'll revise the verbs "to be" and "to have".

Esto significa que, en caso de necesitarlo, tenemos que utilizar los verbos que los complementan.

I want to be able to study (el verbo "want" en inglés requiere el uso de la preposición "to", y por ellos debemos utilizar "be able to" detrás -no podemos decir: I want to can to study)

Verbos Semimodales

Los verbos semimodales, como need, son aquellos que pueden usarse a veces como modales y otras veces como verbos normales. Fíjate en estos ejemplos:

He needn't come: Aquí es modal y por tanto, no emplea auxiliar para negar, va seguido de un verbo en la forma base y no lleva "-s" en la tercera persona del singular del presente simple.
He doesn't need to be here: en este caso es un verbo normal, ya que utiliza auxiliar para negar, lleva "-s" en tercera persona del singular y va seguido de infinitivo con "to".

RESUMEN

must

I must tell you.

He mustn't tell you.

We use must to talk about rules and obligation, or the need to do something. We use mustn't to express prohibition and that something is not right. We sometimes use must and mustn't to recommend something.

Affirmative: subject+ must+ base form of the verb.

You must follow the rules. [obligation]
We must accept the situation. [need]
You must go to the new restaurant. It's great! [recommendation]

We also use must to express certainty- when we are sure something is true.

This must be Jim's brother. He looks just like Jim.

Negative: subject + must not or mustn't+ base form of the verb.

They mustn't use their laptops here. [prohibition]
She mustn't lie to her parents. [not right]

Interrogative: Must + subject+ base form of the verb. This modal verb is not normally used in interrogative sentences.

Must we tell Sally about the party? [need]

Short answers: subject pronoun + must or mustn't.

Must I invite Ben?
Yes, you must. / No, you mustn't.

HAVE TO

Like must, we use have to to talk about rules and obligation or the need to do something. The difference is that "have to" can be conjugated and, therefore, is used in different tenses.

Affirmative: subject+ have I has to+ base form of the verb.

We have to send her an e-mail right now. [obligation]

When we talk about obligation or need in the past, we use had to.

She had to help herfriend yesterday. [need]

Negative: subject+ don't I doesn't+ have to+ base form of the verb. It is used to talk about lack of obligation or need.

You don't have to buy her a present. [lack of obligation]

Note that have to means the same as must, but don't have to and mustn't aren't equivalent.

You don't have to go. [not necessary]
You mustn't go. [prohibition]

Interrogative: Do I Does+ subject+ have to+ base form of the verb.

Do you have to do a test tomorrow? [obligation]

Short answers: subject pronoun + do / does or don't / doesn't.

Do you have to leave now? Yes, I do. / No, I don't.
Does she have to take care of Paul? Yes, she does. / No, she doesn't.

NEED TO

I need to sleep now. He needs to sleep now.

I don't need to sleep now.

He doesn't need to sleep now.

Do you need to sleep now ? Does she need to sleep now? Yes, we do. | No, she doesn't.

Like have to, we use the structure need to to talk about rules and obligation or the need to do something. It can be conjugated and, therefore, is used in different tenses.

Affirmative: subject + need I needs to+ base form of the verb.

We need to return this immediately . [o bligation]

Negative: subject + don't I doesn't + need to+ base form of the verb.

You don't need to do this. [lack of obligation]

Interrogative: Do/Does+ subject + need to+ base form of the verb.

Do you need to go now? [need]

Short answers: subject pronoun+ do I does or don't I doesn't.

Do you need to talk to me? Yes, I do. I No, I don't.
Does he need to finish his work? Yes, he does. I No, he doesn't .

should

I should use it.

He shouldn't use it.

Should you use it?

Yes, we should. / No, she shouldn't.

We use should to give or ask for advice and to talk about duty.

Affirmative: sub ject + should+ base form of the verb.

You should call your parents. [advice]
Tina is in hospital. We should visit her. [duty]

Negative: subject+ should not or shouldn't + base form of the verb.

They shouldn't eat so much junk food . [advice]

Interrogative: Should+ subject+ base form of the verb.

Should I bake a cake? [advice]

Short answers: subject pronoun + should or shouldn't.

Should we leave at six o'clock? Yes, we should. I No, we shouldn't.

CAN

I can swim well.

He can't/ cannot swim well.

Can you swim well?

Yes, we can. / No, she can't.

We use can to express the ability to do something, possibil ity, permission and to make requests.

Affirmative: subject+ can+ base form of the verb.

Lisa can swim very well. [ability]

You can try this. [possibility]

They can go out tonight. [permission]

Negative: subject+ cannot or can't + base form of the verb.

I cannot I can't play the pia no. [ability]

We also use can't to express negative certainty- when we are sure something is impossible.

It can't be true. [negative certainty]

Interrogative: Can+ subject+ base form of the verb.

Can you open the door, please? [request]

Short answers: subject pronoun + can or can't.

Can you play tennis? Yes, I can. | No, I can't.

could

I could play the piano.

He couldn't play the piano.

Could you play the piano?

Yes, we could. / No, she couldn't.

We use could to express ability or possibility in the past and to make polite requests.

Affirmative: subject+ could+ base form of the verb.

Robert could talk when he was one yea r old. [ability]
They could finish the homework on time. [possibility in the past]

Negative: subject+ could not or couldn't+ base form of the verb.

He couldn't swim when he was young. [ability]

Interrogative: Could+ subject+ base form of the verb.

Could you take me home? [request]

Short answers: subject pronoun+ could or couldn't.

Could you do the exam?
Yes, we could. I No, we couldn't .

be able to

Present

I am able to run fast.

He is able to run fast.

We are able to run fast.

I'm not able to run fast.

He isn't able to run fast.

We aren't able to run fast.

Are you able to run fast?

Is he able to run fast?

Are we able to run fast?

Yes, I am. / No, he isn't. / Yes, we are.

Past

I was able to run fast.

He was able to run fast.

We were able to run fast.

I wasn't able to run fast.

He wasn't able to run fast.

We weren't able to run fast.

Were you able to run fast?

Was he able to run fast?

Were we able to run fast?

Yes, I was. / No, he wasn't. / Yes, we were.

Future

I will be able to run fast.

He will be able to run fast.

We will be able to run fast.

I won't be able to run fast.

He won't be able to run fast.

We won't be able to run fast.

Will I be able to run fast?

Will he be able to run fast?

Will we be able to run fast?

Yes, I will./ No, he won't./ Yes, we will.

Like can, we use the structure be able to to talk about possibility and ability. As can is only used in the present tense , we use be able to for all the other tenses .

Affirmative: subject+ to be in the appropriate tense + able to+base form of the verb.

I was able to skate when I was little. [ability]

Negative: subject+ to be in the appropriate tense + not or n't +able to+ base form of the verb.

I won 't be able to get ready in one hour. [possibility]

Interrogative: in the present and past tenses , to be in the appropriate tense +subject+ able to+ base form of the verb. In the future tense will+ subject+ be able to+ base form of the verb.

Are you able to lose weight with the diet? [possibility]

Short answers: in the presen t and past tenses, subject pronoun+ am I is I are or was I were in affirmative and 'm not I isn't I aren't or wasn't I weren't in negative. In the future tense, subject pronoun + will or won't.

Will they be able to find the hotel? Yes, they will. I No, they won't.

may/might

Possibility

I may come.

He may not come.

I might come.

He might not come.

Permission

May I go now?

Yes, you may./ No, you may not.

You may go now.

You may not go now.

We use may and might in affirmative and negative to express possibility in the future, but the use of might indicates that the possibility is more remote. We also use may to express permission in formal speech or to make polite requests.

Affirmative: subject+ may I might+ base form of the verb. I may I might reach my destination today. [p ossi bility] You may use my camera, but don't break it. [permission]

Negative: subject+ may I might+ not+ base form of the verb.