Can / Could
"Can" y "could" se utilizan para expresar permiso, posibilidad o habilidad. Como regla general "can" se utiliza en el presente y "could" en el pasado, pero hay ciertos matices:
a) Posibilidad / habilidad
En el presente "can" y en el pasado "could" o "was / were able".
- With the new motorway you can go from Madrid to Barcelona in less than 4 hours
- Ten years ago you could go from Madrid to Barcelona in 6 hours
- I can play tennis
- I could (was able) to play tennis when I was a child
"Could" también se utiliza con un sentido condicional, mientras que en el futuro se emplea "will be able":
- If I had money I could buy a new car
- In two years I will be able to speak English fluently
b) Permiso
En el presente distinguimos:
- Tener o pedir permiso: "can" tiene un sentido informal y "could" formal.
- I can use the company's car for my private trips (informal)
- I could use the company's car for my private trips (formal)
- Can I borrow your car ? (informal)
- Could I borrow your car ? (formal)
- Dar permiso: se utiliza "can"; "could" únicamente se emplea con un sentido condicional.
- Tonight you can stay with us
- If you don't find any other place, you could stay with
En el pasado se utiliza "could" y en el futuro "can".
c) Ofrecimiento
Sólo se utiliza "can".
- Can I help you?
