English verb conjugation
MUST IMPUGN

Regular verb: impugn - impugned - impugned

Affirmation

Simple form	V-ing form
I must impugn you must impugn he must impugn we must impugn you must impugn they must impugn	I must be impugning you must be impugning he must be impugning we must be impugning you must be impugning they must be impugning
Perfect	V-ing perfect
I must have impugned you must have impugned he must have impugned we must have impugned you must have impugned they must have impugned	I must have been impugning you must have been impugning he must have been impugning we must have been impugning you must have been impugning they must have been impugning

Negation

Simple form	V-ing form
I mustn't impugn you mustn't impugn he mustn't impugn we mustn't impugn you mustn't impugn they mustn't impugn	I mustn't be impugning you mustn't be impugning he mustn't be impugning we mustn't be impugning you mustn't be impugning they mustn't be impugning
Perfect	V-ing perfect
I mustn't have impugned you mustn't have impugned he mustn't have impugned we mustn't have impugned you mustn't have impugned they mustn't have impugned	I mustn't have been impugning you mustn't have been impugning he mustn't have been impugning we mustn't have been impugning you mustn't have been impugning they mustn't have been impugning

Interrogative form

Simple form	V-ing form
must I impugn? must you impugn? must he impugn? must we impugn? must you impugn? must they impugn?	must I be impugning? must you be impugning? must he be impugning? must we be impugning? must you be impugning? must they be impugning?
Perfect	V-ing perfect
must I have impugned? must you have impugned? must he have impugned? must we have impugned? must you have impugned? must they have impugned?	must I have been impugning? must you have been impugning? must he have been impugning? must we have been impugning? must you have been impugning? must they have been impugning?

Interro-negative form

Simple form	V-ing form
mustn't I impugn? mustn't you impugn? mustn't he impugn? mustn't we impugn? mustn't you impugn? mustn't they impugn?	mustn't I be impugning? mustn't you be impugning? mustn't he be impugning? mustn't we be impugning? mustn't you be impugning? mustn't they be impugning?
Perfect	V-ing perfect
mustn't I have impugned? mustn't you have impugned? mustn't he have impugned? mustn't we have impugned? mustn't you have impugned? mustn't they have impugned?	mustn't I have been impugning? mustn't you have been impugning? mustn't he have been impugning? mustn't we have been impugning? mustn't you have been impugning? mustn't they have been impugning?