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 couldn't dam you couldn't dam he couldn't dam we couldn't dam you couldn't dam they couldn't dam	I couldn't be damming you couldn't be damming he couldn't be damming we couldn't be damming you couldn't be damming they couldn't be damming
Perfect	V-ing perfect
I couldn't have dammed you couldn't have dammed he couldn't have dammed we couldn't have dammed you couldn't have dammed they couldn't have dammed	I couldn't have been damming you couldn't have been damming he couldn't have been damming we couldn't have been damming you couldn't have been damming they couldn't 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
couldn't I dam? couldn't you dam? couldn't he dam? couldn't we dam? couldn't you dam? couldn't they dam?	couldn't I be damming? couldn't you be damming? couldn't he be damming? couldn't we be damming? couldn't you be damming? couldn't they be damming?
Perfect	V-ing perfect
couldn't I have dammed? couldn't you have dammed? couldn't he have dammed? couldn't we have dammed? couldn't you have dammed? couldn't they have dammed?	couldn't I have been damming? couldn't you have been damming? couldn't he have been damming? couldn't we have been damming? couldn't you have been damming? couldn't they have been damming?