I must dam you must dam he must dam we must dam you must dam they must dam
V-ing form
I must be damming you must be damming he must be damming we must be damming you must be damming they must be damming
Perfect
I must have dammed you must have dammed he must have dammed we must have dammed you must have dammed they must have dammed
V-ing perfect
I must have been damming you must have been damming he must have been damming we must have been damming you must have been damming they must have been damming
Negation
Simple form
I mustn't dam you mustn't dam he mustn't dam we mustn't dam you mustn't dam they mustn't dam
V-ing form
I mustn't be damming you mustn't be damming he mustn't be damming we mustn't be damming you mustn't be damming they mustn't be damming
Perfect
I mustn't have dammed you mustn't have dammed he mustn't have dammed we mustn't have dammed you mustn't have dammed they mustn't have dammed
V-ing perfect
I mustn't have been damming you mustn't have been damming he mustn't have been damming we mustn't have been damming you mustn't have been damming they mustn't have been damming
Interrogative form
Simple form
must I dam? must you dam? must he dam? must we dam? must you dam? must they dam?
V-ing form
must I be damming? must you be damming? must he be damming? must we be damming? must you be damming? must they be damming?
Perfect
must I have dammed? must you have dammed? must he have dammed? must we have dammed? must you have dammed? must they have dammed?
V-ing perfect
must I have been damming? must you have been damming? must he have been damming? must we have been damming? must you have been damming? must they have been damming?
Interro-negative form
Simple form
mustn't I dam? mustn't you dam? mustn't he dam? mustn't we dam? mustn't you dam? mustn't they dam?
V-ing form
mustn't I be damming? mustn't you be damming? mustn't he be damming? mustn't we be damming? mustn't you be damming? mustn't they be damming?
Perfect
mustn't I have dammed? mustn't you have dammed? mustn't he have dammed? mustn't we have dammed? mustn't you have dammed? mustn't they have dammed?
V-ing perfect
mustn't I have been damming? mustn't you have been damming? mustn't he have been damming? mustn't we have been damming? mustn't you have been damming? mustn't they have been damming?