English verb conjugation
MUST MASTER

Regular verb: master - mastered - mastered

Affirmation

Simple form	V-ing form
I must master you must master he must master we must master you must master they must master	I must be mastering you must be mastering he must be mastering we must be mastering you must be mastering they must be mastering
Perfect	V-ing perfect
I must have mastered you must have mastered he must have mastered we must have mastered you must have mastered they must have mastered	I must have been mastering you must have been mastering he must have been mastering we must have been mastering you must have been mastering they must have been mastering

Negation

Simple form	V-ing form
I mustn't master you mustn't master he mustn't master we mustn't master you mustn't master they mustn't master	I mustn't be mastering you mustn't be mastering he mustn't be mastering we mustn't be mastering you mustn't be mastering they mustn't be mastering
Perfect	V-ing perfect
I mustn't have mastered you mustn't have mastered he mustn't have mastered we mustn't have mastered you mustn't have mastered they mustn't have mastered	I mustn't have been mastering you mustn't have been mastering he mustn't have been mastering we mustn't have been mastering you mustn't have been mastering they mustn't have been mastering

Interrogative form

Simple form	V-ing form
must I master? must you master? must he master? must we master? must you master? must they master?	must I be mastering? must you be mastering? must he be mastering? must we be mastering? must you be mastering? must they be mastering?
Perfect	V-ing perfect
must I have mastered? must you have mastered? must he have mastered? must we have mastered? must you have mastered? must they have mastered?	must I have been mastering? must you have been mastering? must he have been mastering? must we have been mastering? must you have been mastering? must they have been mastering?

Interro-negative form

Simple form	V-ing form
mustn't I master? mustn't you master? mustn't he master? mustn't we master? mustn't you master? mustn't they master?	mustn't I be mastering? mustn't you be mastering? mustn't he be mastering? mustn't we be mastering? mustn't you be mastering? mustn't they be mastering?
Perfect	V-ing perfect
mustn't I have mastered? mustn't you have mastered? mustn't he have mastered? mustn't we have mastered? mustn't you have mastered? mustn't they have mastered?	mustn't I have been mastering? mustn't you have been mastering? mustn't he have been mastering? mustn't we have been mastering? mustn't you have been mastering? mustn't they have been mastering?