English verb conjugation
MUST HUFF

Regular verb: huff - huffed - huffed

Affirmation

Simple form	V-ing form
I must huff you must huff he must huff we must huff you must huff they must huff	I must be huffing you must be huffing he must be huffing we must be huffing you must be huffing they must be huffing
Perfect	V-ing perfect
I must have huffed you must have huffed he must have huffed we must have huffed you must have huffed they must have huffed	I must have been huffing you must have been huffing he must have been huffing we must have been huffing you must have been huffing they must have been huffing

Negation

Simple form	V-ing form
I mustn't huff you mustn't huff he mustn't huff we mustn't huff you mustn't huff they mustn't huff	I mustn't be huffing you mustn't be huffing he mustn't be huffing we mustn't be huffing you mustn't be huffing they mustn't be huffing
Perfect	V-ing perfect
I mustn't have huffed you mustn't have huffed he mustn't have huffed we mustn't have huffed you mustn't have huffed they mustn't have huffed	I mustn't have been huffing you mustn't have been huffing he mustn't have been huffing we mustn't have been huffing you mustn't have been huffing they mustn't have been huffing

Interrogative form

Simple form	V-ing form
must I huff? must you huff? must he huff? must we huff? must you huff? must they huff?	must I be huffing? must you be huffing? must he be huffing? must we be huffing? must you be huffing? must they be huffing?
Perfect	V-ing perfect
must I have huffed? must you have huffed? must he have huffed? must we have huffed? must you have huffed? must they have huffed?	must I have been huffing? must you have been huffing? must he have been huffing? must we have been huffing? must you have been huffing? must they have been huffing?

Interro-negative form

Simple form	V-ing form
mustn't I huff? mustn't you huff? mustn't he huff? mustn't we huff? mustn't you huff? mustn't they huff?	mustn't I be huffing? mustn't you be huffing? mustn't he be huffing? mustn't we be huffing? mustn't you be huffing? mustn't they be huffing?
Perfect	V-ing perfect
mustn't I have huffed? mustn't you have huffed? mustn't he have huffed? mustn't we have huffed? mustn't you have huffed? mustn't they have huffed?	mustn't I have been huffing? mustn't you have been huffing? mustn't he have been huffing? mustn't we have been huffing? mustn't you have been huffing? mustn't they have been huffing?