MODAL VERBS

TABLE OF MODAL AUXILIARY VERBS

• DEFINICIÓN: Los verbos modales son verbos diferentes al resto de los verbos. Tienen una serie de características especiales. Estos verbos pueden expresar: obligación, necesidad, prohibición, ausencia de necesidad, probabilidad, posibilidad, habilidad…
  
• CARACTERÍSTICAS:
  
  • Son verbos incompletos. No tienen participio ni infinitivo, y necesitan otros verbos para completar su conjugación: CAN se completa con la perífrasis BE ABLE TO, MUST con HAVE TO, etc.
    
  • No llevan -S en la 3ª persona singular del presente simple, excepto HAVE TO (HAS TO)
    
  • Todos van seguidos de otro verbo en infinitivo sin TO, excepto OUGHT TO, HAVE TO y NEED TO.
    
  • Como no necesitan verbo auxiliar, construyen la interrogativa invirtiendo el orden del sujeto y el verbo, y la negativa añadiendo NOT. ¡¡OJO!! CANNOT
    

• TABLA DE VERBOS MODALES
  

  	VERB	USE	EXAMPLES	NOTES
  PURE MODALS	CAN (presente)	- Expresar habilidad	- We can drive very well	- Be able to complementa a can cuando indica habilidad y posibilidad: infinitivo, futuro, present perfect y gerundio, e.g. I will be able to play the guitar in a year.
  		- Expresar posibilidad o imposibilidad	- I can't talk, I've got a very sore throat
  		- Expresar o pedir permiso	- Can I sit down?
  		- En negativa expresar deducción y prohibición.	- She can't be at school. It's holiday. - You cannot smoke here.
  	COULD (pasado)	- Expresar habilidad en pasado.	- Jane could drive before she was 18.
  		- Pedir algo educadamente.	- Could you pass the salt, please?
  		- Expresar posibilidad o imposibilidad en el pasado.	- It was so hot I couldn't walk in the sand.
  		- Hacer especulaciones (posibilidad remota)	- This passport could be his.
  		- Hacer sugerencias.	- We could play bingo today.
  		- Remplaza a can en el estilo indirecto	- They said they could do it themselves.
  		- Expresar una crítica.	- You could have bought some more food.
  	MAY (PRE/FUT)	- Pedir algo.	- May I leave the classroom?	- Cuando MAY indica posibilidad indica que algo no es seguro. (quizá, tal vez, puede que)
  		- Expresar permiso.	- You may go to the toilet.
  		- Expresar posibilidad (presente o futura)	- The headmaster may visit the class today.
  		- Hacer especulaciones.	- That may be the thief that was arrested by the police.
  	MIGHT	- Expresar posibilidad (más dudosa)	- They might invite us to the party.	- La posibilidad es muy dudosa (pudiera ser que)
  		- Hacer especulaciones	- They might have broken the window…
  	SHOULD	- Dar y pedir consejos (debería)	- You should do more physical exercise
  		- Expresar obligación moral o que algo no es lo adecuado que esperabamos	- You should be more tolerant
  		- Criticar acciones pasadas	- She should have been quiet
  	WILL	- Hacer un ofrecimiento	- I'll carry the suitcase for you.
  		- Pedir algo educadamente	- Will you bring me a coffee, please?
  	SHALL	- Hacer un ofrecimiento	- Shall I open the window?
  		- Pedir sugerencias	- What shall we do tonight?
  		- Tomar decisiones	- I shall speak to the headmaster
  	WOULD	- Hacer un ofrecimiento	- Would you like some tea?
  		- Rutinas en el pasado (afirm.) (solía)	- When I was a child, I would go fishing.
  	MUST (presente)	- Expresar obligación (autoridad fuerte)	- You must go to school	- HAVE TO complementa a MUST en los tiempos que este carece, e.g. She had to get up early yesterday.
  		- En negativa: expresar prohibición	- You mustn't smoke in hospitals
  		- Expresar deducción (afirmativa)	- They must be happy. They've won the lottery
  	NEED	- Expresar necesidad	- Need we go now?
  		- Con sentido pasivo	- The trees need pruning.
  		- En negativa: ausencia de obligación = don't have to	- You needn't get up early at weekends
  	OUGHT TO	- Dar consejos	- You ought to do more physical exercise
  		- Expresar obligación moral	- You ought to be more tolerant
  	USED TO	- Expresar hábitos o rutinas en el pasado	- I used to play tennis, but now I play basket
  MODALS IDIOMS	HAVE (GOT) TO	- Expresar obligación (+ suave)	- You have to be 18 to drive a car
  		- En negativa: ausencia de obligación	- You don't have to wear a uniform in this school
  	HAD BETTER	- Dar consejos o sugerencia (sería mejor)	- It's getting dark, we'd better go home now
  	WOULD RATHER	- + infinitivo: preferir algo 2 sujetos iguales - + Oración en pasado simple: (preferiría) sujetos diferentes - + infinitivo + than + infinitivo	- I'd rather stay at home (prefiero) - I'd rather she studied harder - I'd rather listen to music than dance
  	BE USED TO + -ING	- Expresa "estar acostumbrado a.."	- I'm used to going to bed late.
  	GET USED TO + -ING	- Expresa " acostumbrarse a.."	- I can't get used to his way of cooking.

  
  

• MODALES PERFECTOS:
  Se refieren al pasado: expresan conclusiones, suposiciones y conjeturas que hacemos sobre hechos pasados y se forman con un modal + have + participio.
  
  • MUST + HAVE + PARTICIPIO → conclusiones lógicas en el pasado, e.g. Sheila was absent yesterday. She must have been ill.
    
  • COULD + HAVE + PARTICIPIO
    

    → indica que hubo posibilidad de hacer algo en el pasado pero realmente no se hizo, e.g. He could have helped us, but he came too late.
    

    → en negativa, expresa la incredulidad de que lo ocurrido sea cierto, e.g. She couldn't have said those words.
    

    → para hacer una suposición en el pasado, e.g. She didn't come to the party. She could have been ill.
    

  • MAY / MIGHT + HAVE + PARTICIPIO → expresan una suposición sobre el pasado, e.g. Call her again. She may / might not have heard you the first time.
    
  • SHOULD / OUGHT TO + HHAVE + PARTICIPIO
    

    → para lamentar que no se siguió un consejo en el pasado, e.g. She looks worse. She should / ought to have seen a doctor last week.
    

    → para lamentar que no se haya cumplido lo que esperábamos, e.g. They should have been home by now.
    

    → en negativa demuestran nuestra opinión crítica sobre algo que no debería haber ocurrido, e.g. I'm very angry with her. She shouldn't have been so rude.
    

    
    

    
    

EXERCISES ON MODAL VERBS
- Exercise 1: Expressing ability
- Exercise 2: Miscellaneous
- Exercise 3: Must / Have to
- Exercise 4: Should / Ought to