English verb conjugation
MUST DOFF

Regular verb: doff - doffed - doffed

Affirmation

Simple form	V-ing form
I must doff you must doff he must doff we must doff you must doff they must doff	I must be doffing you must be doffing he must be doffing we must be doffing you must be doffing they must be doffing
Perfect	V-ing perfect
I must have doffed you must have doffed he must have doffed we must have doffed you must have doffed they must have doffed	I must have been doffing you must have been doffing he must have been doffing we must have been doffing you must have been doffing they must have been doffing

Negation

Simple form	V-ing form
I mustn't doff you mustn't doff he mustn't doff we mustn't doff you mustn't doff they mustn't doff	I mustn't be doffing you mustn't be doffing he mustn't be doffing we mustn't be doffing you mustn't be doffing they mustn't be doffing
Perfect	V-ing perfect
I mustn't have doffed you mustn't have doffed he mustn't have doffed we mustn't have doffed you mustn't have doffed they mustn't have doffed	I mustn't have been doffing you mustn't have been doffing he mustn't have been doffing we mustn't have been doffing you mustn't have been doffing they mustn't have been doffing

Interrogative form

Simple form	V-ing form
must I doff? must you doff? must he doff? must we doff? must you doff? must they doff?	must I be doffing? must you be doffing? must he be doffing? must we be doffing? must you be doffing? must they be doffing?
Perfect	V-ing perfect
must I have doffed? must you have doffed? must he have doffed? must we have doffed? must you have doffed? must they have doffed?	must I have been doffing? must you have been doffing? must he have been doffing? must we have been doffing? must you have been doffing? must they have been doffing?

Interro-negative form

Simple form	V-ing form
mustn't I doff? mustn't you doff? mustn't he doff? mustn't we doff? mustn't you doff? mustn't they doff?	mustn't I be doffing? mustn't you be doffing? mustn't he be doffing? mustn't we be doffing? mustn't you be doffing? mustn't they be doffing?
Perfect	V-ing perfect
mustn't I have doffed? mustn't you have doffed? mustn't he have doffed? mustn't we have doffed? mustn't you have doffed? mustn't they have doffed?	mustn't I have been doffing? mustn't you have been doffing? mustn't he have been doffing? mustn't we have been doffing? mustn't you have been doffing? mustn't they have been doffing?