could dam
Regular verb: dam - dammed- dammed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could dam
you could dam
she could dam
we could dam
you could dam
they could dam 	I could be damming
you could be damming
she could be damming
we could be damming
you could be damming
they could be damming	I could have dammed
you could have dammed
she 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
she 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 couldn't dam
you couldn't dam
she 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
she couldn't be damming
we couldn't be damming
you couldn't be damming
they couldn't be damming	I couldn't have dammed
you couldn't have dammed
she 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
she 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 	Perfect 	V-ing perfect 	
could I dam?
could you dam?
could she dam?
could we dam?
could you dam?
could they dam? 	could I be damming?
could you be damming?
could she be damming?
could we be damming?
could you be damming?
could they be damming? 	could I have dammed?
could you have dammed?
could she 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 she 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 	
couldn't I dam?
couldn't you dam?
couldn't she 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 she be damming?
couldn't we be damming?
couldn't you be damming?
couldn't they be damming? 	couldn't I have dammed?
couldn't you have dammed?
couldn't she 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 she have been damming?
couldn't we have been damming?
couldn't you have been damming?
couldn't they have been damming?