I can dam you can dam he can dam we can dam you can dam they can dam
V-ing form
I can be damming you can be damming he can be damming we can be damming you can be damming they can be damming
Perfect
I can have dammed you can have dammed he can have dammed we can have dammed you can have dammed they can have dammed
V-ing perfect
I can have been damming you can have been damming he can have been damming we can have been damming you can have been damming they can have been damming
Negation
Simple form
I cannot dam you cannot dam he cannot dam we cannot dam you cannot dam they cannot dam
V-ing form
I cannot be damming you cannot be damming he cannot be damming we cannot be damming you cannot be damming they cannot be damming
Perfect
I cannot have dammed you cannot have dammed he cannot have dammed we cannot have dammed you cannot have dammed they cannot have dammed
V-ing perfect
I cannot have been damming you cannot have been damming he cannot have been damming we cannot have been damming you cannot have been damming they cannot have been damming
Interrogative form
Simple form
can I dam? can you dam? can he dam? can we dam? can you dam? can they dam?
V-ing form
can I be damming? can you be damming? can he be damming? can we be damming? can you be damming? can they be damming?
Perfect
can I have dammed? can you have dammed? can he have dammed? can we have dammed? can you have dammed? can they have dammed?
V-ing perfect
can I have been damming? can you have been damming? can he have been damming? can we have been damming? can you have been damming? can they have been damming?
Interro-negative form
Simple form
can I not dam? can you not dam? can he not dam? can we not dam? can you not dam? can they not dam?
V-ing form
can I not be damming? can you not be damming? can he not be damming? can we not be damming? can you not be damming? can they not be damming?
Perfect
can I not have dammed? can you not have dammed? can he not have dammed? can we not have dammed? can you not have dammed? can they not have dammed?
V-ing perfect
can I not have been damming? can you not have been damming? can he not have been damming? can we not have been damming? can you not have been damming? can they not have been damming?