English verb conjugation
MUST RETURN

Regular verb: return - returned - returned

Affirmation

Simple form	V-ing form
I must return you must return he must return we must return you must return they must return	I must be returning you must be returning he must be returning we must be returning you must be returning they must be returning
Perfect	V-ing perfect
I must have returned you must have returned he must have returned we must have returned you must have returned they must have returned	I must have been returning you must have been returning he must have been returning we must have been returning you must have been returning they must have been returning

Negation

Simple form	V-ing form
I mustn't return you mustn't return he mustn't return we mustn't return you mustn't return they mustn't return	I mustn't be returning you mustn't be returning he mustn't be returning we mustn't be returning you mustn't be returning they mustn't be returning
Perfect	V-ing perfect
I mustn't have returned you mustn't have returned he mustn't have returned we mustn't have returned you mustn't have returned they mustn't have returned	I mustn't have been returning you mustn't have been returning he 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	V-ing form
must I return? must you return? must he return? must we return? must you return? must they return?	must I be returning? must you be returning? must he be returning? must we be returning? must you be returning? must they be returning?
Perfect	V-ing perfect
must I have returned? must you have returned? must he have returned? must we have returned? must you have returned? must they have returned?	must I have been returning? must you have been returning? must he have been returning? must we have been returning? must you have been returning? must they have been returning?

Interro-negative form

Simple form	V-ing form
mustn't I return? mustn't you return? mustn't he return? mustn't we return? mustn't you return? mustn't they return?	mustn't I be returning? mustn't you be returning? mustn't he be returning? mustn't we be returning? mustn't you be returning? mustn't they be returning?
Perfect	V-ing perfect
mustn't I have returned? mustn't you have returned? mustn't he have returned? mustn't we have returned? mustn't you have returned? mustn't they have returned?	mustn't I have been returning? mustn't you have been returning? mustn't he have been returning? mustn't we have been returning? mustn't you have been returning? mustn't they have been returning?