English verb conjugation
COULD RESPOND

Regular verb: respond - responded - responded

Affirmation

Simple form	V-ing form
I could respond you could respond he could respond we could respond you could respond they could respond	I could be responding you could be responding he could be responding we could be responding you could be responding they could be responding
Perfect	V-ing perfect
I could have responded you could have responded he could have responded we could have responded you could have responded they could have responded	I could have been responding you could have been responding he could have been responding we could have been responding you could have been responding they could have been responding

Negation

Simple form	V-ing form
I could not respond you could not respond he could not respond we could not respond you could not respond they could not respond	I could not be responding you could not be responding he could not be responding we could not be responding you could not be responding they could not be responding
Perfect	V-ing perfect
I could not have responded you could not have responded he could not have responded we could not have responded you could not have responded they could not have responded	I could not have been responding you could not have been responding he could not have been responding we could not have been responding you could not have been responding they could not have been responding

Interrogative form

Simple form	V-ing form
could I respond? could you respond? could he respond? could we respond? could you respond? could they respond?	could I be responding? could you be responding? could he be responding? could we be responding? could you be responding? could they be responding?
Perfect	V-ing perfect
could I have responded? could you have responded? could he have responded? could we have responded? could you have responded? could they have responded?	could I have been responding? could you have been responding? could he have been responding? could we have been responding? could you have been responding? could they have been responding?

Interro-negative form

Simple form	V-ing form
could I not respond? could you not respond? could he not respond? could we not respond? could you not respond? could they not respond?	could I not be responding? could you not be responding? could he not be responding? could we not be responding? could you not be responding? could they not be responding?
Perfect	V-ing perfect
could I not have responded? could you not have responded? could he not have responded? could we not have responded? could you not have responded? could they not have responded?	could I not have been responding? could you not have been responding? could he not have been responding? could we not have been responding? could you not have been responding? could they not have been responding?