Verbos modales
Los modales (can, must, should, might…) añaden obligación, consejo, capacidad o grado de seguridad al verbo. En las partes 2 y 4 salen sin parar, sobre todo las deducciones y las formas con have + participio para el pasado.
Obligación, necesidad y consejo
- must / have to
Obligación. Must suele ser la que siente quien habla; have to, una norma externa. Must solo vale para el presente; en pasado y futuro, had to y will have to.
- I must remember to call my mother tonight.
- We have to wear a uniform at work.
- We had to wait for an hour.
- mustn't / don't have to
Mustn't = está prohibido. Don't have to = no hace falta.
- You mustn't use your phone during the exam.
- You don't have to come if you're busy.
- needn't have + participio / didn't need to
Needn't have = lo hiciste y no hacía falta. Didn't need to = no hacía falta, normalmente no lo hiciste.
- You needn't have bought milk because we already had some.
- I didn't need to take a taxi, so I walked.
- should / ought to / had better
Consejo. Had better avisa de una consecuencia y se refiere al presente o al futuro.
- You should see a doctor about that cough.
- You'd better leave now or you'll miss the train.
- be supposed to
Lo que se espera o está previsto, aunque a veces no se cumpla.
- We are supposed to check in two hours before the flight.
Capacidad
- can / could / be able to
Could para una capacidad general en el pasado. Para un logro en una ocasión concreta, was able to o managed to.
- My grandmother could speak four languages.
- After three hours, the firefighters were able to put out the fire.
Deducción
- must / can't + infinitivo
Presente: estás seguro de que sí o de que no.
- She must be at home because her car is outside.
- That can't be Tom; he's in Paris this week.
- might / may / could + infinitivo
Presente o futuro: es posible.
- Take a jacket because it might get cold later.
- must / can't / might / may / could + have + participio
Deducción sobre el pasado: seguro que sí, seguro que no, quizá.
- They must have forgotten about the meeting.
- He can't have seen us, or he would have waved.
- She could have missed the bus.
- should have / could have + participio
Crítica o posibilidad del pasado que no se cumplió.
- You should have told me you were ill.
- You could have hurt yourself.
Dónde aparece en el examen
- Parte 2: faltan must, can't, have (de must have), able, better o need.
- Parte 4: I'm sure she isn't at work → She can't be at work; It's possible he forgot → He might have forgotten.
- Parte 4: You brought food, but it wasn't necessary → You needn't have brought food; It was a mistake to sell the car → I shouldn't have sold the car.
- Parte 1: opciones como manage, succeed y able, que significan lo mismo pero llevan estructuras distintas (managed to, succeeded in, was able to).
Trampas típicas
- Los modales no llevan -s ni to: She can swim. Ought to lleva to; have to no es modal y sí lleva -s: He has to go.
- Para la deducción negativa de presente, usa can't, no mustn't: It can't be true.
- Couldn't vale para una ocasión concreta en negativa: I couldn't open the door.
- Con have + participio, el modal habla del pasado: must have gone, no must went.
Ojo.«No tienes que venir» significa que no hace falta. You mustn't come significaría «tienes prohibido venir». ✗ You mustn't come if you're busy. ✓ You don't have to come if you're busy.
Ojo.Por influencia de «tener que», se añade to detrás de must. ✗ She must to leave early today. ✓ She must leave early today.
Dónde cae en el examen
- Parte 1 · Multiple-choice cloze , con ejercicios de muestra
- Parte 2 · Open cloze , con ejercicios de muestra
- Parte 4 · Key word transformation , con ejercicios de muestra