English verb conjugation
MUST BELIEVE

Regular verb: believe - believed - believed

Affirmation

Simple form	V-ing form
I must believe you must believe he must believe we must believe you must believe they must believe	I must be believing you must be believing he must be believing we must be believing you must be believing they must be believing
Perfect	V-ing perfect
I must have believed you must have believed he must have believed we must have believed you must have believed they must have believed	I must have been believing you must have been believing he must have been believing we must have been believing you must have been believing they must have been believing

Negation

Simple form	V-ing form
I mustn't believe you mustn't believe he mustn't believe we mustn't believe you mustn't believe they mustn't believe	I mustn't be believing you mustn't be believing he mustn't be believing we mustn't be believing you mustn't be believing they mustn't be believing
Perfect	V-ing perfect
I mustn't have believed you mustn't have believed he mustn't have believed we mustn't have believed you mustn't have believed they mustn't have believed	I mustn't have been believing you mustn't have been believing he mustn't have been believing we mustn't have been believing you mustn't have been believing they mustn't have been believing

Interrogative form

Simple form	V-ing form
must I believe? must you believe? must he believe? must we believe? must you believe? must they believe?	must I be believing? must you be believing? must he be believing? must we be believing? must you be believing? must they be believing?
Perfect	V-ing perfect
must I have believed? must you have believed? must he have believed? must we have believed? must you have believed? must they have believed?	must I have been believing? must you have been believing? must he have been believing? must we have been believing? must you have been believing? must they have been believing?

Interro-negative form

Simple form	V-ing form
mustn't I believe? mustn't you believe? mustn't he believe? mustn't we believe? mustn't you believe? mustn't they believe?	mustn't I be believing? mustn't you be believing? mustn't he be believing? mustn't we be believing? mustn't you be believing? mustn't they be believing?
Perfect	V-ing perfect
mustn't I have believed? mustn't you have believed? mustn't he have believed? mustn't we have believed? mustn't you have believed? mustn't they have believed?	mustn't I have been believing? mustn't you have been believing? mustn't he have been believing? mustn't we have been believing? mustn't you have been believing? mustn't they have been believing?