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