English verb conjugation
COULD DAM

Regular verb: dam - dammed - dammed

Affirmation

Simple form	V-ing form
I could dam you could dam he could dam we could dam you could dam they could dam	I could be damming you could be damming he could be damming we could be damming you could be damming they could be damming
Perfect	V-ing perfect
I could have dammed you could have dammed he could have dammed we could have dammed you could have dammed they could have dammed	I could have been damming you could have been damming he could have been damming we could have been damming you could have been damming they could have been damming

Negation

Simple form	V-ing form
I could not dam you could not dam he could not dam we could not dam you could not dam they could not dam	I could not be damming you could not be damming he could not be damming we could not be damming you could not be damming they could not be damming
Perfect	V-ing perfect
I could not have dammed you could not have dammed he could not have dammed we could not have dammed you could not have dammed they could not have dammed	I could not have been damming you could not have been damming he could not have been damming we could not have been damming you could not have been damming they could not have been damming

Interrogative form

Simple form	V-ing form
could I dam? could you dam? could he dam? could we dam? could you dam? could they dam?	could I be damming? could you be damming? could he be damming? could we be damming? could you be damming? could they be damming?
Perfect	V-ing perfect
could I have dammed? could you have dammed? could he have dammed? could we have dammed? could you have dammed? could they have dammed?	could I have been damming? could you have been damming? could he have been damming? could we have been damming? could you have been damming? could they have been damming?

Interro-negative form

Simple form	V-ing form
could I not dam? could you not dam? could he not dam? could we not dam? could you not dam? could they not dam?	could I not be damming? could you not be damming? could he not be damming? could we not be damming? could you not be damming? could they not be damming?
Perfect	V-ing perfect
could I not have dammed? could you not have dammed? could he not have dammed? could we not have dammed? could you not have dammed? could they not have dammed?	could I not have been damming? could you not have been damming? could he not have been damming? could we not have been damming? could you not have been damming? could they not have been damming?