English verb conjugation
MUST FIRE

Regular verb: fire - fired - fired

Affirmation

Simple form	V-ing form
I must fire you must fire he must fire we must fire you must fire they must fire	I must be firing you must be firing he must be firing we must be firing you must be firing they must be firing
Perfect	V-ing perfect
I must have fired you must have fired he must have fired we must have fired you must have fired they must have fired	I must have been firing you must have been firing he must have been firing we must have been firing you must have been firing they must have been firing

Negation

Simple form	V-ing form
I mustn't fire you mustn't fire he mustn't fire we mustn't fire you mustn't fire they mustn't fire	I mustn't be firing you mustn't be firing he mustn't be firing we mustn't be firing you mustn't be firing they mustn't be firing
Perfect	V-ing perfect
I mustn't have fired you mustn't have fired he mustn't have fired we mustn't have fired you mustn't have fired they mustn't have fired	I mustn't have been firing you mustn't have been firing he mustn't have been firing we mustn't have been firing you mustn't have been firing they mustn't have been firing

Interrogative form

Simple form	V-ing form
must I fire? must you fire? must he fire? must we fire? must you fire? must they fire?	must I be firing? must you be firing? must he be firing? must we be firing? must you be firing? must they be firing?
Perfect	V-ing perfect
must I have fired? must you have fired? must he have fired? must we have fired? must you have fired? must they have fired?	must I have been firing? must you have been firing? must he have been firing? must we have been firing? must you have been firing? must they have been firing?

Interro-negative form

Simple form	V-ing form
mustn't I fire? mustn't you fire? mustn't he fire? mustn't we fire? mustn't you fire? mustn't they fire?	mustn't I be firing? mustn't you be firing? mustn't he be firing? mustn't we be firing? mustn't you be firing? mustn't they be firing?
Perfect	V-ing perfect
mustn't I have fired? mustn't you have fired? mustn't he have fired? mustn't we have fired? mustn't you have fired? mustn't they have fired?	mustn't I have been firing? mustn't you have been firing? mustn't he have been firing? mustn't we have been firing? mustn't you have been firing? mustn't they have been firing?