I could prealter you could prealter he could prealter we could prealter you could prealter they could prealter
Forma con V-ing
I could be prealtering you could be prealtering he could be prealtering we could be prealtering you could be prealtering they could be prealtering
Perfecto
I could have prealtered you could have prealtered he could have prealtered we could have prealtered you could have prealtered they could have prealtered
Perfecto con V-ing
I could have been prealtering you could have been prealtering he could have been prealtering we could have been prealtering you could have been prealtering they could have been prealtering
Negación
Forma simple
I could not prealter you could not prealter he could not prealter we could not prealter you could not prealter they could not prealter
Forma con V-ing
I could not be prealtering you could not be prealtering he could not be prealtering we could not be prealtering you could not be prealtering they could not be prealtering
Perfecto
I could not have prealtered you could not have prealtered he could not have prealtered we could not have prealtered you could not have prealtered they could not have prealtered
Perfecto con V-ing
I could not have been prealtering you could not have been prealtering he could not have been prealtering we could not have been prealtering you could not have been prealtering they could not have been prealtering
Forma interrogativa
Forma simple
could I prealter? could you prealter? could he prealter? could we prealter? could you prealter? could they prealter?
Forma con V-ing
could I be prealtering? could you be prealtering? could he be prealtering? could we be prealtering? could you be prealtering? could they be prealtering?
Perfecto
could I have prealtered? could you have prealtered? could he have prealtered? could we have prealtered? could you have prealtered? could they have prealtered?
Perfecto con V-ing
could I have been prealtering? could you have been prealtering? could he have been prealtering? could we have been prealtering? could you have been prealtering? could they have been prealtering?
Forma interro-negativa
Forma simple
could I not prealter? could you not prealter? could he not prealter? could we not prealter? could you not prealter? could they not prealter?
Forma con V-ing
could I not be prealtering? could you not be prealtering? could he not be prealtering? could we not be prealtering? could you not be prealtering? could they not be prealtering?
Perfecto
could I not have prealtered? could you not have prealtered? could he not have prealtered? could we not have prealtered? could you not have prealtered? could they not have prealtered?
Perfecto con V-ing
could I not have been prealtering? could you not have been prealtering? could he not have been prealtering? could we not have been prealtering? could you not have been prealtering? could they not have been prealtering?