English verb conjugation
MUST FUNCTION

Regular verb: function - functioned - functioned

Affirmation

Simple form	V-ing form
I must function you must function he must function we must function you must function they must function	I must be functioning you must be functioning he must be functioning we must be functioning you must be functioning they must be functioning
Perfect	V-ing perfect
I must have functioned you must have functioned he must have functioned we must have functioned you must have functioned they must have functioned	I must have been functioning you must have been functioning he must have been functioning we must have been functioning you must have been functioning they must have been functioning

Negation

Simple form	V-ing form
I mustn't function you mustn't function he mustn't function we mustn't function you mustn't function they mustn't function	I mustn't be functioning you mustn't be functioning he mustn't be functioning we mustn't be functioning you mustn't be functioning they mustn't be functioning
Perfect	V-ing perfect
I mustn't have functioned you mustn't have functioned he mustn't have functioned we mustn't have functioned you mustn't have functioned they mustn't have functioned	I mustn't have been functioning you mustn't have been functioning he mustn't have been functioning we mustn't have been functioning you mustn't have been functioning they mustn't have been functioning

Interrogative form

Simple form	V-ing form
must I function? must you function? must he function? must we function? must you function? must they function?	must I be functioning? must you be functioning? must he be functioning? must we be functioning? must you be functioning? must they be functioning?
Perfect	V-ing perfect
must I have functioned? must you have functioned? must he have functioned? must we have functioned? must you have functioned? must they have functioned?	must I have been functioning? must you have been functioning? must he have been functioning? must we have been functioning? must you have been functioning? must they have been functioning?

Interro-negative form

Simple form	V-ing form
mustn't I function? mustn't you function? mustn't he function? mustn't we function? mustn't you function? mustn't they function?	mustn't I be functioning? mustn't you be functioning? mustn't he be functioning? mustn't we be functioning? mustn't you be functioning? mustn't they be functioning?
Perfect	V-ing perfect
mustn't I have functioned? mustn't you have functioned? mustn't he have functioned? mustn't we have functioned? mustn't you have functioned? mustn't they have functioned?	mustn't I have been functioning? mustn't you have been functioning? mustn't he have been functioning? mustn't we have been functioning? mustn't you have been functioning? mustn't they have been functioning?