English verb conjugation
MUST BURN

Regular verb: burn - burned - burned

Affirmation

Simple form	V-ing form
I must burn you must burn he must burn we must burn you must burn they must burn	I must be burning you must be burning he must be burning we must be burning you must be burning they must be burning
Perfect	V-ing perfect
I must have burned you must have burned he must have burned we must have burned you must have burned they must have burned	I must have been burning you must have been burning he must have been burning we must have been burning you must have been burning they must have been burning

Negation

Simple form	V-ing form
I mustn't burn you mustn't burn he mustn't burn we mustn't burn you mustn't burn they mustn't burn	I mustn't be burning you mustn't be burning he mustn't be burning we mustn't be burning you mustn't be burning they mustn't be burning
Perfect	V-ing perfect
I mustn't have burned you mustn't have burned he mustn't have burned we mustn't have burned you mustn't have burned they mustn't have burned	I mustn't have been burning you mustn't have been burning he mustn't have been burning we mustn't have been burning you mustn't have been burning they mustn't have been burning

Interrogative form

Simple form	V-ing form
must I burn? must you burn? must he burn? must we burn? must you burn? must they burn?	must I be burning? must you be burning? must he be burning? must we be burning? must you be burning? must they be burning?
Perfect	V-ing perfect
must I have burned? must you have burned? must he have burned? must we have burned? must you have burned? must they have burned?	must I have been burning? must you have been burning? must he have been burning? must we have been burning? must you have been burning? must they have been burning?

Interro-negative form

Simple form	V-ing form
mustn't I burn? mustn't you burn? mustn't he burn? mustn't we burn? mustn't you burn? mustn't they burn?	mustn't I be burning? mustn't you be burning? mustn't he be burning? mustn't we be burning? mustn't you be burning? mustn't they be burning?
Perfect	V-ing perfect
mustn't I have burned? mustn't you have burned? mustn't he have burned? mustn't we have burned? mustn't you have burned? mustn't they have burned?	mustn't I have been burning? mustn't you have been burning? mustn't he have been burning? mustn't we have been burning? mustn't you have been burning? mustn't they have been burning?