I must return you must return she must return we must return you must return they must return
V-ing form
I must be returning you must be returning she must be returning we must be returning you must be returning they must be returning
Perfect
I must have returned you must have returned she must have returned we must have returned you must have returned they must have returned
V-ing perfect
I must have been returning you must have been returning she must have been returning we must have been returning you must have been returning they must have been returning
Negation
Simple form
I mustn't return you mustn't return she mustn't return we mustn't return you mustn't return they mustn't return
V-ing form
I mustn't be returning you mustn't be returning she mustn't be returning we mustn't be returning you mustn't be returning they mustn't be returning
Perfect
I mustn't have returned you mustn't have returned she mustn't have returned we mustn't have returned you mustn't have returned they mustn't have returned
V-ing perfect
I mustn't have been returning you mustn't have been returning she mustn't have been returning we mustn't have been returning you mustn't have been returning they mustn't have been returning
Interrogative form
Simple form
must I return? must you return? must she return? must we return? must you return? must they return?
V-ing form
must I be returning? must you be returning? must she be returning? must we be returning? must you be returning? must they be returning?
Perfect
must I have returned? must you have returned? must she have returned? must we have returned? must you have returned? must they have returned?
V-ing perfect
must I have been returning? must you have been returning? must she have been returning? must we have been returning? must you have been returning? must they have been returning?
Interro-negative form
Simple form
mustn't I return? mustn't you return? mustn't she return? mustn't we return? mustn't you return? mustn't they return?
V-ing form
mustn't I be returning? mustn't you be returning? mustn't she be returning? mustn't we be returning? mustn't you be returning? mustn't they be returning?
Perfect
mustn't I have returned? mustn't you have returned? mustn't she have returned? mustn't we have returned? mustn't you have returned? mustn't they have returned?
V-ing perfect
mustn't I have been returning? mustn't you have been returning? mustn't she have been returning? mustn't we have been returning? mustn't you have been returning? mustn't they have been returning?