English verb conjugation
MUST CHUFF

Regular verb: chuff - chuffed - chuffed

Affirmation

Simple form	V-ing form
I must chuff you must chuff he must chuff we must chuff you must chuff they must chuff	I must be chuffing you must be chuffing he must be chuffing we must be chuffing you must be chuffing they must be chuffing
Perfect	V-ing perfect
I must have chuffed you must have chuffed he must have chuffed we must have chuffed you must have chuffed they must have chuffed	I must have been chuffing you must have been chuffing he must have been chuffing we must have been chuffing you must have been chuffing they must have been chuffing

Negation

Simple form	V-ing form
I mustn't chuff you mustn't chuff he mustn't chuff we mustn't chuff you mustn't chuff they mustn't chuff	I mustn't be chuffing you mustn't be chuffing he mustn't be chuffing we mustn't be chuffing you mustn't be chuffing they mustn't be chuffing
Perfect	V-ing perfect
I mustn't have chuffed you mustn't have chuffed he mustn't have chuffed we mustn't have chuffed you mustn't have chuffed they mustn't have chuffed	I mustn't have been chuffing you mustn't have been chuffing he mustn't have been chuffing we mustn't have been chuffing you mustn't have been chuffing they mustn't have been chuffing

Interrogative form

Simple form	V-ing form
must I chuff? must you chuff? must he chuff? must we chuff? must you chuff? must they chuff?	must I be chuffing? must you be chuffing? must he be chuffing? must we be chuffing? must you be chuffing? must they be chuffing?
Perfect	V-ing perfect
must I have chuffed? must you have chuffed? must he have chuffed? must we have chuffed? must you have chuffed? must they have chuffed?	must I have been chuffing? must you have been chuffing? must he have been chuffing? must we have been chuffing? must you have been chuffing? must they have been chuffing?

Interro-negative form

Simple form	V-ing form
mustn't I chuff? mustn't you chuff? mustn't he chuff? mustn't we chuff? mustn't you chuff? mustn't they chuff?	mustn't I be chuffing? mustn't you be chuffing? mustn't he be chuffing? mustn't we be chuffing? mustn't you be chuffing? mustn't they be chuffing?
Perfect	V-ing perfect
mustn't I have chuffed? mustn't you have chuffed? mustn't he have chuffed? mustn't we have chuffed? mustn't you have chuffed? mustn't they have chuffed?	mustn't I have been chuffing? mustn't you have been chuffing? mustn't he have been chuffing? mustn't we have been chuffing? mustn't you have been chuffing? mustn't they have been chuffing?