I could know you could know she could know we could know you could know they could know
Forma con V-ing
I could be knowing you could be knowing she could be knowing we could be knowing you could be knowing they could be knowing
Perfecto
I could have known you could have known she could have known we could have known you could have known they could have known
Perfecto con V-ing
I could have been knowing you could have been knowing she could have been knowing we could have been knowing you could have been knowing they could have been knowing
Negación
Forma simple
I could not know you could not know she could not know we could not know you could not know they could not know
Forma con V-ing
I could not be knowing you could not be knowing she could not be knowing we could not be knowing you could not be knowing they could not be knowing
Perfecto
I could not have known you could not have known she could not have known we could not have known you could not have known they could not have known
Perfecto con V-ing
I could not have been knowing you could not have been knowing she could not have been knowing we could not have been knowing you could not have been knowing they could not have been knowing
Forma interrogativa
Forma simple
could I know? could you know? could she know? could we know? could you know? could they know?
Forma con V-ing
could I be knowing? could you be knowing? could she be knowing? could we be knowing? could you be knowing? could they be knowing?
Perfecto
could I have known? could you have known? could she have known? could we have known? could you have known? could they have known?
Perfecto con V-ing
could I have been knowing? could you have been knowing? could she have been knowing? could we have been knowing? could you have been knowing? could they have been knowing?
Forma interro-negativa
Forma simple
could I not know? could you not know? could she not know? could we not know? could you not know? could they not know?
Forma con V-ing
could I not be knowing? could you not be knowing? could she not be knowing? could we not be knowing? could you not be knowing? could they not be knowing?
Perfecto
could I not have known? could you not have known? could she not have known? could we not have known? could you not have known? could they not have known?
Perfecto con V-ing
could I not have been knowing? could you not have been knowing? could she not have been knowing? could we not have been knowing? could you not have been knowing? could they not have been knowing?