Warning, this verb may not exist. Conjugation is given as example.
Affirmation
Simple form
I must fiance you must fiance he must fiance we must fiance you must fiance they must fiance
V-ing form
I must be fiancing you must be fiancing he must be fiancing we must be fiancing you must be fiancing they must be fiancing
Perfect
I must have fianced you must have fianced he must have fianced we must have fianced you must have fianced they must have fianced
V-ing perfect
I must have been fiancing you must have been fiancing he must have been fiancing we must have been fiancing you must have been fiancing they must have been fiancing
Negation
Simple form
I mustn't fiance you mustn't fiance he mustn't fiance we mustn't fiance you mustn't fiance they mustn't fiance
V-ing form
I mustn't be fiancing you mustn't be fiancing he mustn't be fiancing we mustn't be fiancing you mustn't be fiancing they mustn't be fiancing
Perfect
I mustn't have fianced you mustn't have fianced he mustn't have fianced we mustn't have fianced you mustn't have fianced they mustn't have fianced
V-ing perfect
I mustn't have been fiancing you mustn't have been fiancing he mustn't have been fiancing we mustn't have been fiancing you mustn't have been fiancing they mustn't have been fiancing
Interrogative form
Simple form
must I fiance? must you fiance? must he fiance? must we fiance? must you fiance? must they fiance?
V-ing form
must I be fiancing? must you be fiancing? must he be fiancing? must we be fiancing? must you be fiancing? must they be fiancing?
Perfect
must I have fianced? must you have fianced? must he have fianced? must we have fianced? must you have fianced? must they have fianced?
V-ing perfect
must I have been fiancing? must you have been fiancing? must he have been fiancing? must we have been fiancing? must you have been fiancing? must they have been fiancing?
Interro-negative form
Simple form
mustn't I fiance? mustn't you fiance? mustn't he fiance? mustn't we fiance? mustn't you fiance? mustn't they fiance?
V-ing form
mustn't I be fiancing? mustn't you be fiancing? mustn't he be fiancing? mustn't we be fiancing? mustn't you be fiancing? mustn't they be fiancing?
Perfect
mustn't I have fianced? mustn't you have fianced? mustn't he have fianced? mustn't we have fianced? mustn't you have fianced? mustn't they have fianced?
V-ing perfect
mustn't I have been fiancing? mustn't you have been fiancing? mustn't he have been fiancing? mustn't we have been fiancing? mustn't you have been fiancing? mustn't they have been fiancing?