Modal Verbs

Verbos modais, também chamados auxiliares modais ou simplesmente modais são utilizados na construções de frases para expressar: uma capacidade, uma possibilidade, uma necessidade ou outra condição. E também funcionam como auxiliares na formação de perguntas junto ao verbo principal (que deve estar no infinitivo, exceto ought).

Eles não possuem particípio nem infinitivo, não são flexionados nas terceiras pessoas do singular no presente e são incompletos, ou seja, precisam de outros verbos para completar sua conjugação. 

Os principais verbos modais em inglês são 10:

Can		Could
May		Might
Shall		Should
Will		Would
Must		Ought (to)

Ordem de uso em frase afirmativa:

SUJEITO + MODAL + VERBO PRINCIPAL

They can come.

Mike should walk.

  

Questões fechadas (cuja respostas são: sim / não):

MODAL +SUJEITO + VERBO PRINCIPAL

Can they come?

Should Mike walk?

Questões abertas:

WH QUESTIONS + MODAL +SUJEITO + VERBO PRINCIPAL

When Can they come?

Where Should Mike walk?

 

http://www.blogger.com/blogger

Podemos expressar nossas ideias em linguagem formal e informal. Para fazer isso bem, precisamos aprender a formação dessas frases que comumente se utilizam os verbos modais.

• I can ride a horse. (ability)
• We can stay with my brother when we are in Paris. (opportunity)
• She cannot stay out after 10 PM. (permission)
• Can you hand me the stapler? (request)
• Any child can grow up to be president. (possibility)

1. Polite Requests with " I " as The Subject.

MODAL VERB	EXAMPLE/S	EXPLANATION
May I ... ? Could I ... ?	May I (please) borrow your pen? Could I borrow your pen (please)?	May I and Could I are used to request permission. They are equally polite. Note: In a polite request, could has a present or future meaning, not a past meaning. Might is also possible: Might I borrow your pen? Might I is quite formal and polite; it is used much less frequently than May I and Could I.
Can I ... ?	Can I borrow your pen?	Can I is used informally to request permission, especially if the speaker is talking to someone s/he knows fairly well. Can I is usually considered a little less polite than May I or Could I.
Response:	Certainly. Yes, certainly. Of course. Yes, of course. Sure. (informal)	Often the response to a polite request is an action, such as a nod or shake of the head, or a simple "uh-huh."

2. Polite Requests with "You" as The Subject

MODAL VERB	EXAMPLE/S	EXPLANATION
Would You ... ? Will you ... ?	Would you pass the salt (please)? Will you (please) pass the salt?	The meaning of would you and will you in a polite request is the same. Would you is more common and is often considered more polite. The degree of politeness, however, is often determined by the speaker's tone of voice.
Could you ...?	Could you pass the salt (please)?	Basically, could you and would you have the same meaning. The difference is slight. Would you = Do you want to do this please? Could you = Do you want to do this please, and Is it possible for you to do this? Could you and would you are equally polite.
Can you ...?	Can you (please) pass the salt?	Can you is often used informally. It usually sounds less polite than could you or would you.
Response:	Yes, I'd ( I would ) be happy to Yes, I'd ( I would ) be glad to. Certainly Sure. (informal)	A person usually responds in the affirmative to a polite request. If a negative response is necessary,a person might begin by saying "I'd like to, but...." (e.g I'd like to pass the salt, but I can't reach it").

http://tx.english-ch.com

Formas Gerais de Uso

Modal	Example	Uses
Can	They can control their own budgets. We can’t fix it. Can I smoke here? Can you help me?	Ability / Possibility Inability / Impossibility Asking for permission Request
Could	Could I borrow your dictionary? Could you say it again more slowly? We could try to fix it ourselves. I think we could have another Gulf War. He gave up his old job so he could work for us.	Asking for permission. Request Suggestion Future possibility Ability in the past
May	May I have another cup of coffee? China may become a major economic power.	Asking for permission Future possibility
Might	We'd better phone tomorrow, they might be eating their dinner now. They might give us a 10% discount.	Present possibility Future possibility
Must	We must say good-bye now. They mustn’t disrupt the work more than necessary.	Necessity / Obligation Prohibition
Ought to	We ought to employ a professional writer.	Saying what’s right or correct
Shall (More common in the UK than the US)	Shall I help you with your luggage? Shall we say 2.30 then? Shall I do that or will you?	Offer Suggestion Asking what to do
Should	We should sort out this problem at once. I think we should check everything again. Profits should increase next year.	Saying what’s right or correct Recommending action Uncertain prediction
Will	I can’t see any taxis so I’ll walk. I'll do that for you if you like. I’ll get back to you first thing on Monday. Profits will increase next year.	Instant decisions Offer Promise Certain prediction
Would	Would you mind if I brought a colleague with me? Would you pass the salt please? Would you mind waiting a moment? "Would three o`clock suit you?" - "That’d be fine." Would you like to play golf this Friday? "Would you prefer tea or coffee?" - "I’d like tea please."	Asking for permission Request Request Making arrangements Invitation Preferences

http://www.learnenglish.de

Em alguns momentos torna-se desnecessário o uso dos modais, nesse caso, é possível fazer as seguintes substituições:

Modal Verb	Substitute	Example
must	to have to	I must swim. = I have to swim.
must not	not to be allowed to	I must not swim. = I am not allowed to swim.
can	to be able to	I can swim. = I am able to swim.
may	to be allowed to	I may swim. = I am allowed to swim.
need	to have to	I need to swim. = I have to swim.
need not	not to have to	I need not swim. = I don't have to swim.
shall / should/ ought to	to be supposed to / to be expected to / to be to	I shall / should / ought to swim. = I am supposed to swim. / I am expected to swim. / I am to swim.

http://tx.english-ch.com