I could exchange you could exchange he could exchange we could exchange you could exchange they could exchange
Forma con V-ing
I could be exchanging you could be exchanging he could be exchanging we could be exchanging you could be exchanging they could be exchanging
Perfecto
I could have exchanged you could have exchanged he could have exchanged we could have exchanged you could have exchanged they could have exchanged
Perfecto con V-ing
I could have been exchanging you could have been exchanging he could have been exchanging we could have been exchanging you could have been exchanging they could have been exchanging
Negación
Forma simple
I couldn't exchange you couldn't exchange he couldn't exchange we couldn't exchange you couldn't exchange they couldn't exchange
Forma con V-ing
I couldn't be exchanging you couldn't be exchanging he couldn't be exchanging we couldn't be exchanging you couldn't be exchanging they couldn't be exchanging
Perfecto
I couldn't have exchanged you couldn't have exchanged he couldn't have exchanged we couldn't have exchanged you couldn't have exchanged they couldn't have exchanged
Perfecto con V-ing
I couldn't have been exchanging you couldn't have been exchanging he couldn't have been exchanging we couldn't have been exchanging you couldn't have been exchanging they couldn't have been exchanging
Forma interrogativa
Forma simple
could I exchange? could you exchange? could he exchange? could we exchange? could you exchange? could they exchange?
Forma con V-ing
could I be exchanging? could you be exchanging? could he be exchanging? could we be exchanging? could you be exchanging? could they be exchanging?
Perfecto
could I have exchanged? could you have exchanged? could he have exchanged? could we have exchanged? could you have exchanged? could they have exchanged?
Perfecto con V-ing
could I have been exchanging? could you have been exchanging? could he have been exchanging? could we have been exchanging? could you have been exchanging? could they have been exchanging?
Forma interro-negativa
Forma simple
couldn't I exchange? couldn't you exchange? couldn't he exchange? couldn't we exchange? couldn't you exchange? couldn't they exchange?
Forma con V-ing
couldn't I be exchanging? couldn't you be exchanging? couldn't he be exchanging? couldn't we be exchanging? couldn't you be exchanging? couldn't they be exchanging?
Perfecto
couldn't I have exchanged? couldn't you have exchanged? couldn't he have exchanged? couldn't we have exchanged? couldn't you have exchanged? couldn't they have exchanged?
Perfecto con V-ing
couldn't I have been exchanging? couldn't you have been exchanging? couldn't he have been exchanging? couldn't we have been exchanging? couldn't you have been exchanging? couldn't they have been exchanging?