Qu'est-ce que c'est ?
Can, can't, could et couldn't sont des verbes modaux.
Ils sont utilisés pour parler :
- de la capacité au présent
- de la capacité au passé
- de la permission
- des demandes
- de la possibilité
Can est la forme positive.
- I can swim.
Can't est la forme contractée de cannot.
- I can't drive.
Could est souvent utilisé pour la capacité au passé ou les demandes polies.
- She could read when she was four.
- Could you help me?
Couldn't est la forme contractée de could not.
- We couldn't find the address.
Quand utiliser
Utilisez can pour la capacité au présent.
- He can speak English.
- I can cook.
Utilisez can't quand quelqu'un n'est pas capable de faire quelque chose.
- She can't swim.
- We can't come today.
Utilisez can pour demander ou donner la permission.
- Can I use your phone?
- You can leave early.
Utilisez could pour la capacité générale au passé.
- I could run fast when I was younger.
- They could speak French as children.
Utilisez couldn't pour l'absence de capacité ou une situation infructueuse au passé.
- He couldn't read the sign.
- We couldn't open the door.
Utilisez can ou could pour faire des demandes.
- Can you close the window?
- Could you close the window?
Could est généralement plus poli que can dans les demandes.
Structure
Utilisez la forme de base du verbe après can, can't, could et couldn't.
| Forme | Structure | Exemple |
|---|---|---|
| Présent positif | sujet + can + verbe de base | She can drive. |
| Présent négatif | sujet + can't + verbe de base | She can't drive. |
| Passé positif | sujet + could + verbe de base | She could drive at eighteen. |
| Passé négatif | sujet + couldn't + verbe de base | She couldn't drive last year. |
La forme est la même pour chaque sujet.
- I can swim.
- He can swim.
- They can swim.
N'ajoutez pas -s après he, she ou it.
Questions
Utilisez :
Can/Could + sujet + verbe de base ?
| Type de question | Exemple |
|---|---|
| Capacité au présent | Can you swim? |
| Permission | Can I sit here? |
| Demande | Can you help me? |
| Demande polie | Could you help me? |
| Capacité au passé | Could she read at five? |
Réponses courtes
- Can you drive? — Yes, I can.
- Can he come? — No, he can't.
- Could they swim? — Yes, they could.
- Could she open it? — No, she couldn't.
Exemples
- I can speak a little Spanish.
- She can't come to work today.
- Can you help me with this box?
- Can I open the window?
- You can use my computer.
- He could swim when he was five.
- We couldn't find a taxi last night.
- Could you speak more slowly, please?
- They could not hear the announcement.
- My brother can cook very well.
Exceptions
Utilisez could pour la capacité générale au passé.
- She could play the piano when she was young.
Pour une action réussie spécifique au passé, was able to est souvent plus naturel.
- We were able to fix the problem yesterday.
Cependant, couldn't est naturel pour une action spécifique infructueuse.
- We couldn't fix the problem yesterday.
Cannot s'écrit en un seul mot.
- Correct : cannot
- Incorrect : can not
La forme can not n'est possible que lorsque not appartient à une autre phrase, mais cet usage est rare.
Erreurs courantes
-
Incorrect : She cans swim. Correct : She can swim. Explication : N'ajoutez pas -s aux verbes modaux.
-
Incorrect : I can to drive. Correct : I can drive. Explication : Utilisez le verbe de base sans to après can.
-
Incorrect : He could speaks English. Correct : He could speak English. Explication : Utilisez la forme de base après could.
-
Incorrect : Do you can help me? Correct : Can you help me? Explication : N'utilisez pas do dans les questions avec can.
-
Incorrect : I don't can swim. Correct : I can't swim. Explication : Utilisez can't, pas don't can.
-
Incorrect : She could to read at four. Correct : She could read at four. Explication : N'utilisez pas to après could.
-
Incorrect : Can you helped me? Correct : Can you help me? Explication : Utilisez la forme de base du verbe après can.
-
Incorrect : I couldn't found my keys. Correct : I couldn't find my keys. Explication : Utilisez la forme de base après couldn't.