I could reply you could reply he could reply we could reply you could reply they could reply
Forma con V-ing
I could be replying you could be replying he could be replying we could be replying you could be replying they could be replying
Perfecto
I could have replied you could have replied he could have replied we could have replied you could have replied they could have replied
Perfecto con V-ing
I could have been replying you could have been replying he could have been replying we could have been replying you could have been replying they could have been replying
Negación
Forma simple
I could not reply you could not reply he could not reply we could not reply you could not reply they could not reply
Forma con V-ing
I could not be replying you could not be replying he could not be replying we could not be replying you could not be replying they could not be replying
Perfecto
I could not have replied you could not have replied he could not have replied we could not have replied you could not have replied they could not have replied
Perfecto con V-ing
I could not have been replying you could not have been replying he could not have been replying we could not have been replying you could not have been replying they could not have been replying
Forma interrogativa
Forma simple
could I reply? could you reply? could he reply? could we reply? could you reply? could they reply?
Forma con V-ing
could I be replying? could you be replying? could he be replying? could we be replying? could you be replying? could they be replying?
Perfecto
could I have replied? could you have replied? could he have replied? could we have replied? could you have replied? could they have replied?
Perfecto con V-ing
could I have been replying? could you have been replying? could he have been replying? could we have been replying? could you have been replying? could they have been replying?
Forma interro-negativa
Forma simple
could I not reply? could you not reply? could he not reply? could we not reply? could you not reply? could they not reply?
Forma con V-ing
could I not be replying? could you not be replying? could he not be replying? could we not be replying? could you not be replying? could they not be replying?
Perfecto
could I not have replied? could you not have replied? could he not have replied? could we not have replied? could you not have replied? could they not have replied?
Perfecto con V-ing
could I not have been replying? could you not have been replying? could he not have been replying? could we not have been replying? could you not have been replying? could they not have been replying?