could dam
Regular verb: dam - dammed- dammed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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	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 	Perfect 	V-ing perfect 	
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	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 	Perfect 	V-ing perfect 	
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? 	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 	Perfect 	V-ing perfect 	
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? 	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?